Yeah the AAU thing, it doesn't really drive this at all. ND would have been in the big ten any point they wanted without it.
I'm not saying its a given, but it's a lot more likely then I think people around Nebraska are willing to let themselves acknowledge. I don't want it either, but there is no way a conference turns down Texas if they get rid of it. Texas can very much pick their spot. They are sitting on mountains of money in one of the biggest states in the country. Hell they can pick the spot of a friend or two (or 3 in the pac's case) depending on the friends.
Texas is a cancer. Is the money worth the risk that your 110 year old conference will emplode in 10-20 years? No chance it is. Definately not with ND still out there. The B1G is far from hard up. It's not like the Big12 we just left, and Texas isn't the only fish in the seas. The ONLY thing Texas has going for it will be their money - which we have plenty of as-is. As this plays out, and after A&M leaves and airs out some dirty laundry, Texas will have to beg one of the Pac12/B1G/SEC conferences to let them in. Heck, A&M probably will have a clause in their SEC agreement that prevents Texas from joining. Why leave a conference because of an entity only to see that entity follow you. They'll be guarding against that.
We all know what Texas is, but that didn't stop the big 8 members from turning into Disney cartoons with dollar signs spinning in their eyes as they caved to Texas's demands on the conference's formation. It won't stop that from happening with other conferences either.
Texas is more of a prize then ND, it's positioned between the conferences that will definitely still exist when the dust settles in one of the biggest states with huge TV markets they make more money then any athletic department. They can pick where they end up if they are willing to give up/make concessions on the LHN and anyone who believes otherwise is being silly.
As far as a "clause that prevents texas from joining" LOL, uhh no, no conference is going to allow someone to join and day one dictate who they might add as other members. The SEC would tell them to get bent, same as the big ten would with us if Nebraska had started naming terms to them on who they could or could not add if they expanded.