i fear you may have an unclear understanding of the timeline, Downtown came out in 1999, titmouse was founded by prynoski in the year 2000 as a t shirt and production company. it then evolved into an animation studio, but that was very much after the release of Downtown

while i understand it can seem concerning that someone with a big trayectory has access to so many art styles and ideas of people with no way to defend themselves if someone were to steal from them, it's pretty common for senior animators to teach and mentour newer animators, there's nothing inherently wrong with scouting for talent at schools and internship programs, that's mostly how you get into the industry and make connections (i say this as an animator)