That's really more of a speculative archaeological question than a historical question. Evidence of fairly advanced alcohol fermentation (to the extent of experimenting with flavor additives) has been observed in Chinese pottery dating from prehistoric times, with similar discoveries in Mesopotamia.

Determining whether prehistoric humans migrating to what is now China brought this technology with them, or discovered it independently, is probably impossible since it predates writing.

Approaching the question instead from a from a food science perspective: Fermentation is pretty much impossible not to discover, since it's a spontaneous natural process that's vital to food preservation. The process for making crude beer is nearly identical to the process for preserving food for the winter. Any civilization that stores food, even a nomadic one, would have learned it in some form.

It would be more surprising to find a neolithic culture or civilization that forgot fermentation. It would require a civilization not preserve or store their food while still maintaining food security.

Check out Patrick McGovern's 2004 paper "Fermented beverages of pre- and proto-historic China" for some interesting reading on the archaeology. Sandor Katz's "The Art of Fermentation" is a great intro to the science and history of fermentation for a general reader, and is very well sourced if you're interested in the scholarship behind it.