because of which school he went to.
I CAN imagine one of the following two things:
1. They thought he was too small (or otherwise not worth an offer) and the school had virtually nothing to do with it.
2. He was right near the breaking point of offer/no-offer, and while a similar player at a school where BYU is trying to make inroads or keep a coach happy might end up getting an offer, this player's school didn't give him that additional bump.
In other words, while I don't believe which school a player attended has much to do with anything, I could imagine it making a difference only at the very margins.