Don't forget to factor that in. Now, with a two point return, all they have to do is make one drive for a tie with the same amount of time on the clock as before the decision to kick or kneel was made. As opposed to having to drive the length of the field once, score, successfully kick an onside kick, and drive another half-field length in that same amount of time. At the end of a game, time is just as much an enemy as the opponent. And ASU had already killed all their timeouts. Two scoring drives with the amount of time left is less likely than one scoring drive.

And you're also not factoring in the the momentum that would have swung in ASU's favor or the doubt and anxiety that may have crept into BYU's minds had the blocked kick took place.