The B1G would take Oklahoma in a heartbeat, no hesitation. Texas and Oklahoma are the only two Gold Standard programs still up for grabs in CR. If the B1G or SEC captures both programs, they will soar to diminance over the other conferences. If TX and OK are split between the B1G and SEC, there will be some equalibrium between the two.
The B1G and SEC will pull out all the stops when the Big 12 GoR expires. Their respective TV partners will join the fray. The stakes are enormous.
The B1G recently reorganized the CIC. U. of Chicago wanted a structure that would insulate them from close association with schools of lesser academic standing. People sprculate that this was done to allow Oklahoma to join the B1G. I further speculate that it could also allow entry of Ok State, if that were required to land the Sooners. The B1G cannot afford to see TX and OK both land in the SEC. The inverse is also true.
The demise of the Big 12 is IMHO no long in question. I often wonder if OK and TX have already made backdoor agreements with one conference or the other.