players heard the whistles and others didn't. The resulting Retzlaff scramble and chucking the ball out of the side of the endzone is not what would have happened without whistles. I know Utah fans thought they had won, but the play was clearly being stopped.
Even ESPN/ABC said similar in their article:
"Prior to the fourth-down play, BYU snapped the ball and Retzlaff was flushed out of the end zone, but Sitake had called a timeout before the snap, likely saving the game in the process."
Likely saving the game? We don't know how that play would have gone sans whistles.
Here is one link, I also saw it on ESPN: