In choosing the championship match up, so conferences don't necessarily have to select the winners of the divisions, but rather can select whom they deem are the best two teams. It will pass because overall it will give the P5 conferences more power to decide when it comes to championship games. The issue of 12 teams is secondary and apparently will not to voted upon separately. Bad news for byu.
There might be some other political pressure by the other P5 conferences for the Big12 to go to 12, but it doesn't sound like this vote will help.