Whatever happens with the TV contract, the Big 12 is an autonomous conference that will continue receiving its full shall of CFP distribution. In 2019, that base amount was $67M; there are five years left on CFP contract.
Any team that leaves, will not partake of the exit fees, which combined will be in the $100M-$150M range.
No one is leaving thst kind of money behind.
The AAC is the conference in trouble. The Big 12 will likely poach 2 and as many as 5 of its schools.