I don't think there is an Ivy League policy of assault charges. Cornell, maybe. I think he is planning to "greyshirt," so that could factor in.
(I have personally seen students have their admissions to less competitive institutions revoked for lesser things. I now Mike Grey has spoke, but he is not in admissions and that was before charges were filed. The kid may end up fine or they could say "admission based on good behavior over gap year" or any number of things.)