Doing my research for a doc project on the mapuche peoples, I stumbled upon a young mapuche man, who feels fairly certain that his great-great-grandfather was exhibited at the "Mapuche" display of the infamous human zoo that was organized in 1883 in Paris.
Indeed, his grandmother told him that her grandfather was brought to Europe by a German man alongside his family, and that they lived in a park alongside a group of "savages who ate raw meat and spoke an incomprehensible language".
This indeed seems to fit with the events, as the Mapuche were brought to France by one Richard Fritz, and were exhibited next to a Selk'nam family (from the southern tip of South America) with whom they were asked to interact by anthropologists.
I am truly stunned by this story, and wished to know if there have ever been other stories told by people exhibited in human zoos. Being exposed as objects for the pleasure of Europeans, I find it quite moving to finally hear their voices, even if it's more than a century too late.
Sounds like you're looking more for sources than an answer, so I would have a few places to suggest. Two books on the topic that I have handy are:
Michael C. Hawkins. Semi-Civilized: The Moro Village at the Louisiana Purchase Exposition. Northern Illinois University Press, 2020.
Parezo, Nancy J.., Fowler, Don D.. Anthropology Goes to the Fair: The 1904 Louisiana Purchase Exposition. University of Nebraska Press, 2007.
They are secondary sources, and as Parezo notes, sources which offer insight into the participants' thoughts are somewhat rare, but these do, on the whole, a good job weaving together sources and offering insight into the topic, and giving those put on display at least some voice, even if it might not be wholly them. So either of these would be good places to look for better understanding of that you are asking.