The only way he comes back is if he's told he won't go in the 1st round.
Your part about him coming back and the perception of a top 3 pick falling out of the lottery would 100% be used by other coaches competing with BYU for recruits.
TBH, there is a 100% chance he's a 1st rounder and a 95.348 chance he's a top 8 pick.