A few thoughts about this.
The Big 12 GOR can't be renewed/extended unless all teams agree. If it is true that Oklahoma wants to go to the Big Ten then they will continue to not agree and will be free to leave without penalty for the 2025 season. If they go, I think Texas goes too. WHERE they go is the question, so they might end up in the Big Ten but might end up elsewhere. If they end up in the Big Ten I wouldn't worry about them throwing their weight around though. The Big 12 had an unequal power structure due to the unequal revenue sharing and the concentration of teams in Texas that voted as a bloc, that's not the case in the Big Ten. They won't have any more say in how things are done than OSU does now - and if anyone thinks they have more say than Iowa or Northwestern just look at how revenue splits for away game gates are done which is clearly to the disadvantage of teams like OSU/PSU/Michigan with monster stadiums.
The Longhorn Network isn't the issue some people think it is. ESPN is losing $5-$10 million a year on it, they would likely PAY to get out of the contract early. Texas would be totally happy with a lump sum payment and an immediate full share of Big Ten revenue (they'd get that concession for joining due to what they bring...not a slight on Nebraska but like Iowa your team is in a state with a small population that's nowhere near as attractive for TV as Texas) Texas is getting $15 million a year for Longhorn, and BTN's payouts including profit sharing are close enough to that now they'll probably exceed that number by 2025. So Texas wouldn't lose anything even if they walked away from Longhorn with no payout from ESPN.
As for pods, also not a concern. We'll almost certainly have an 8 team playoff by then, and the only way I see that as being workable is if they force conferences to drop the conference championship game (otherwise they'll be meaningless for a top 3 team who might choose to sit their best players since they know they are in either way) Let the Big Ten winner be decided the old fashioned way, by the best record (plus tiebreakers which could include the playoff committee's ranking) Then you don't have to figure out a pod system to work around the rivalries and stuff, instead you give each team 2 or 3 protected rivalries and round robin the rest.
Yes, the schedules won't be equal since you don't all play the same teams but that's already the case in the divisions, and across the divisions, so what else is new? If a really great Iowa or Nebraska team went undefeated in the Big Ten and so did Ohio State because they didn't play that year (like what happened to Iowa in 2002) and the playoff committee ranks Ohio State higher, like they probably would, it is no problem because you have the two at large bids to fall back on. The third bid would be to the top G5 team, aka the "shut up Boise State and UCF fans, we'll give you Alabama and watch you get destroyed" bid.