Maybe so, maybe not.
If there is no Big 12 (take that, Baylor), there may be no exit penalty. And if the four schools mentioned choose to kill the Big 12, won’t they get to pay, too?
Lotsa legal maneuvering to come.
The Aggies left the Big 12 while the Big 12 still exists and the Aggies will have to pay the exit penalty.
Texas, OU, Tech and OSU will simply dissolve the Big 12 and take the money.