devtrackers.gg
Believe it or not, there once was a mega sloth in North America that humans may have actually met (depending on the margin of when it died out and when humans came to America). Thomas Jefferson had a set of paw bones of one, and (not knowing what it was) instructed lewis and Clark to be on the lookout for a very large lion creature on their journey.
Yes, this is the animal that's in the game. Its real name is megatherium.
As I recall the leading hypothesis was it that it was humans who killed them (along with all the other animals in the Americas bigger than a buffalo), so they definitely met. This was based on there being a steady population of megatheria for millions of years and then all suddenly vanishing at the same time after the aboriginals arrived. Here's a list of them:
https://en.wikipedia.org/wiki/List_of_North_American_animals_extinct_in_the_Holocene
There used to be a bunch of really wild giant animal species in the Americas up until people arrived. I figured in the future maybe someone would bring some of them back. Makes me think I should add wooly mammoths and saber-toothed cats.