The dances are more of a general Region VI thing (as in, you're guaranteed to hear all three at any conference in the Region) The word modifications to American Pie originate from Alpha Alpha @ UIUC. Since your section chair is an alum of that chapter, he'd be a good person to ask
The "acting" in American Pie are unique things to Eta Sigma and Alpha Alpha Eta (two chapters in the same town), so only someone from one of those two chapters could really explain it to you. Sol is just Sol