Do we know how the Big 12 allocates the revenue from its media contracts? Specifically, does anybody know how much money Oklahoma receives for all of its games including its private network, and how much Texas gets for theirs (including the LHN)? I'm assuming the league doesn't give every school an equal share.

If we are comparing the B1G or SEC payout to the average payout to Big 12 members, we may be overestimating the incentive the Sooners would have to switch.
Texas has no need to go anywhere, at least as long as OU stays put (and maybe even if they don't). If OU decides to stay, there's no reason for anybody to move.