This is a great question. In my opinion, it's totally plausible that a large number of enslaved persons in a region would have known about the reputation of a particularly harsh plantation. Since this is a hypothetical, I can only speak in generalities about enslaved peoples' access to geopolitical knowledge. I'll start with a few examples of historians who speak about this issue, and then move to a discussion of how this might have worked in practice in the world of Django.

Historian Philip Troutman describes a slave "grapevine" that carried a great volume of rumor and news. His example for the existence of a "grapevine" is the 1841 revolt on the Creole ship, where a group of slaves revolted and steered the ship to the Bahamas. Knowing that slavery had been outlawed in the British colonies, they understood that they would have a chance of freedom in the Bahamas. According to Troutman, this demonstrates their "geopolitical literacy."

Another example of how this "grapevine" flowed was the African American and enslaved response to the Haitian Revolution. Historian Julius Scott has demonstrated how information spread about this event among communities of African descent throughout North America and the Caribbean. The speed and breadth of news dissemination about this event among slaves and free blacks in the western hemisphere that Scott shows is really breathtaking. In fact, rumors were so potent that at some times, slave revolts throughout North America and the Atlantic world were often premised on rumors of events happening elsewhere.

Indeed, enslaved peoples' mental maps seem to have been based in large part on the apparent freedom of a space or its unfreedom. In the eighteenth century, slaves in North America were sometimes threatened with being sent to the West Indies, where it was understood that sugar production exacted a harsher toll on slaves. For many slaves, this was seen as a death sentence. On the other hand, some spaces were simply safe havens. For example, a runaway slave named Leonard Black stated that even though he did not know if Boston was a state or city, he knew that it represented liberation. Moreover, being informed about certain owners and plantations could be a form of resistance. As historian Walter Johnson has shown, slaves in the antebellum New Orleans slave market performed in certain ways to either make themselves appealing to certain kinds of owners, or else prevent other owners from purchasing them. It doesn't take much of an imaginative leap to wonder if slaves who were aware of the bad reputation of certain owners would have made themselves seem unappealing in the slave pen.

So how did slaves come to develop this geopolitical literacy? Probably not through reading. Slave masters and governments tended to police literacy and print very closely to prevent slaves from learning much about the outside world (Frederick Douglass remembered that "Nothing seemed to make her more angry than to see me with a newspaper" and Henry Bibb, in his slave narrative, recalled "the only source of information that I had to enlighten my mind, consisted in what I could see and hear from others. Slaves were not allowed books, pen, ink, nor paper."). Nevertheless, some slaves took advantage of opportunities to read books and newspapers. Frederick Douglass certainly did. Julius Scott reports on a case of slaves working for a Charleston newspaper in 1793, who took 200 copies of each issue for their own use, and presumably to disseminate among other literate slaves.

One of the keys to the "grapevine" was oral communication. As Julius Scott wrote, "black cultural traditions that favored speech and white laws that restricted literacy gave a continuing primacy to other channels of communication." (115) Naturally, the other key was the mobility of the enslaved. Slave plantations were not isolated islands. Slaves moved between plantations often, bringing all kinds of information with them. Some slave masters were surprisingly permissive about allowing slaves to socialize between plantations. Some even permitted slaves to regularly visit a family member in an adjacent plantation. Some slaves likely did this without a master's permission. Runaways, especially if they were apprehended, also brought back all kinds of knowledge that could be fed into the "grapevine."

Moreover, there was a significant amount of movement between urban and rural environments for slaves. Slaves were probably especially well-informed in cities, where oral reports and printed news circulated widely. Relatively well-informed free blacks and sailors tended to congregate in cities. Their knowledge could find its way into a plantation easily. Free and urban blacks often came into contact with transient slaves. The most important slave markets in antebellum America were in urban spaces like Charleston and New Orleans. A slave who had just arrived from one of these urban centers might carry information or rumor about a plantation that he or she had been sold from, or had heard about from another enslaved person in a slave pen. Moreover, it wasn't uncommon in some parts of the South for a slave to be sent to a city to earn a temporary wage, if he wasn't needed in the plantation. Indeed, this happened to Frederick Douglass.

Overall, it's easy to imagine that a slave in Candyland would have been resold and spread rumors about it. It's also easy to imagine that these rumors would have been of great interest to slaves listening, who would have repeated the rumor as they moved between plantations. If this rumor reached the node of an urban environment like New Orleans, it probably would have spread even more rapidly throughout the plantation South. The "grapevine" would have likely picked up on rumors of a particularly heinous plantation, and spread it around the South with remarkable efficiency.

Sources:

• Philip Troutman, "Grapevine in the Slave Market: African American Geopolitical Literacy and the 1841 Creole Revolt," in The Chattel Principle, edited by Walter Johnson (New Haven: Yale University Press, 2004).
• Gilbert Osofsky, editor, Puttin’ on Ole Massa (New York: Harpers & Row, 1969), 17. [Leonard Black]
• Walter Johnson. Soul by Soul: Life Inside the Antebellum Slave Market (Cambridge: Harvard University Press, 1999), ch. 6.
• Julius Sherrard Scott, III, “The Common Wind: Currents of Afro-American Communication in the Era of the Haitian Revolution,” (Ph.D. diss., Duke University, 1986).

[by the way, Scott's dissertation, if you can get ahold of it, and Johnson's book are two of my favorite works of history focusing on slavery, if anyone feels like reading further]

I don't know about in America, but in 18th early 19th century Trinidad, slaves from different plantation regularly got together for dances and festivals. However, they started cracking down after the Haitian Revolution and on Trinidad they ended up executing a bunch of slaves they thought were planning a Revolution.

Source: The Scandal of Colonial Rule, James Epstein

Can't recommend this book enough. It reads almost like a novel but with sources. It covers one of the most sensational trials of early 19th century England (where the trial took place) and played an important part in ending slavery in the British Empire. Here is a synopsis.

In 1806 General Thomas Picton, Britain's first governor of Trinidad, was brought to trial for the torture of a free mulatto named Louisa Calderon and for overseeing a regime of terror over the island's slave population. James Epstein offers a fascinating account of the unfolding of this colonial drama. He shows the ways in which the trial and its investigation brought empire 'home' and exposed the disjuncture between a national self-image of humane governance and the brutal realities of colonial rule. He uses the trial to open up a range of issues, including colonial violence and norms of justice, the status of the British subject, imperial careering, visions of development after slavery, slave conspiracy and the colonial archive. He reveals how Britain's imperial regime became more authoritarian, hierarchical and militarised but also how unease about abuses of power and of the rights of colonial subjects began to grow.

It took me quite awhile to find my source since I had forgotten the name, but on google books Life on the Old Plantation in Antebellum Days: Or, A Story Based On Facts is a very interesting read. It was written by a preacher born as a slave in 1850, and as far as I can find one of few examples of its kind. Right in the first chapter the author describes the plantations adjoining his own and the names of the owners, and mentions that no one was mistreated in the area. The author lists names and dates in great detail, and tells how slaves met at church as well as for communal chores such as felling trees. In this manner everyone knew everyone's business. I really recommend reading it!
https://books.google.com/books?id=3EcWAAAAYAAJ&dq=slaves+life+plantation&source=gbs_navlinks_s

Slaves fulfilled the roles of attendants and servants-- they were maids, drivers/coachmen, errand runners, as such they accompanied their owner and owner's family members on visiting and shopping expeditions, as well as being sent off to take things to or collect things from various tradespeople. While the free people socialized, the servants would be sent to the kitchen for a meal or the stables to take care of the horses. This naturally afforded plenty of opportunities to talk with resident slaves and slaves of other visitors.