I believe that TX and OU still have voting rights in the Big12, even on the new members thing. We just didn't have the votes to block it so why even bother? If you read the wording of when a school loses their votes its on formal notification of leaving, which IIRC is 18 months written notice. Assuming a negotiated settlement doesn't show up first, we'll put in written notification of leaving for summer of 2025 in winter of 2023. Until then, everyone knows the score publicly, but the reason UT and OU spokespeople have been very careful to talk about "remaining a member of the Big12" and "we're fulfilling our obligations as a Big12 member" is so not to provide lawsuit fodder in the other direction.
On the sovereign immunity thing, can anyone cite any case regarding conference affiliation where any state institution relied on sovereign immunity to break a GoR unilaterally and without consequence? This seems like the message board realignment Macguffin, the magical answer that will solve all our problems forever! Except if it's so all powerful and wonderful, why hasn't it been used already? Why does literally nobody outside of message board randoms talk about it?