If the Pac12 DOES call the Big12 to verify, and your future conference mates catch wind. BYU would instantly have a black mark, and if any of the "BYU was difficult to deal with" stuff is true from the last time, we only prove it.
BYU should accept and call Larry Scott and tell him what a loser he is for missing out, then spend the rest of our energy whooping on P12 opponents.