Again, you are uninformed. The previous govt administration in Oklahoma always made it to where Oklahoma can't go anywhere without taking Oklahoma State.
The big brother has to take the little brother and no SEC move was really possible taking Ok St. Now, for whatever reason that's no longer a requirement.
Texas vs Texas a&m is a rivalry but it's not OU vs TX level. This is about money. So yeah y'all can separate from Texas, but OU/TX is major money. Both schools know that
In the end, this whole move is about money.