Mizzou's big problem is that the Big 10 is holding out for ND. Period. They took Nebraska and shortly thereafter Nebraska is dropped from the AAU.
Mizzou is more of a prize than ISU. I see the Big 10 taking Mizzou before ISU. I just don't know if I see the Big 10 taking anyone right now. They don't have to.
SEC might move cautiously as well. Would Texas go to the SEC??
The Real Aggressor in the whole situation is PAC 12 IMO. They want to expand real bad into Texas/Oklahoma and create an Eastern Division of 8 teams.
The Big 12 is all about Texas/Oklahoma. Always has been. Lose one and you lose it all. The Big 12 is not a BCS AQ without either one of them.
If the Big 12 folds then a vacuum will be created. IMO, the Big East can fill that vacuum quite nicely and pick up the revenues (or at least part of them) that the Big 12 was getting. Eventually the 2 or 3 best teams will fill the vacuum that the top teams of the Big 12 held. That is the way it goes.
People seem to forget that when the Big 12 was formed there were loads of teams in the Top 25. The North was actually considered to be the cream of the conference with Colorado, Nebraska, Kansas State, along with Mizzou, Kansas, and ISU.