Why yes, They even use Maya. In fact I have a Alias|Wavefront 98 Siggrapah t-shirt with Cartmen on it. This
was back when they used Power Animator. (Pre Maya)
I posted the Cell shader question because your recent post kind-of reminded me of that South Park look. That's a good thing.

again great work man. I realy liked the anim.

Here's a link to an article on Alias and South Park.
https://www.mayaassociation.fsbusines...-southpark.htm