It wouldn't. ESPN/Fox is just trying to leverage who gets in (or maybe just pay more for what they have), but if it did here's how you win that legal argument.

Since ESPN/Fox knew (or should have known) that all the other P5 leagues (who are all contracted with ESPN/Fox) have contracts which include GOR for the foreseeable future, the only way for the Big 12 to expand would be to add programs not in the P5. The contract language in question could only realistically apply to the schools outside the P5.

Since it was clear what type of schools would be available to be added to the Big 12, and because the schools being discussed are at least equal to the other schools which have moved up to P5 conferences, there is no way that language would not apply.