I think a 1 loss team from the PAC12 or Big12 gets left out. The Big10 champion has to have 2 losses to be left out. tOSU would have to stub their toe somewhere along the way. Oklahoma plays nobody so 1 loss leaves them out.
I suppose it’s possible that the SEC runner-up gets left out if they lose to Georgia by more than we did AND Georgia goes undefeated.