The Big 12 needs 12 teams in order to avoid another opportunity at disaster like the last two years.
And since Texas has nowhere to go now due to the LHN and since Oklahoma can't go to the Pac-16 without Texas, OU and Texas lack the leverage to make the other teams do their bidding (which is why Mizzo might stay in the Big 12 where it at least has a chance at success rather than the SEC, especially since the B1G is not going to come calling).
With BYU being 10, the real question becomes No. 11 and No. 12. Every school in the Big 12 except for Texas benefits from the addition of TCU. Louisville is not coming, as it really values basketball more than football (not a bunch more, but just enough) and the Cards will benefit from Big East 3.0 with a bunch of CUSA teams.
WV most likely will be in the SEC, in spite of the alleged rejection. The SEC has no other viable options except for CUSA schools (yeah, they could get ECU or Houston --- which would make the Houston metro a strong SEC market instead of a contested one).
Of course, there is a private school in Texas that would fit in the SEC.......