If Nebraska accepts, the Big TEN is at 12 and does not need to go further.
But now the BIG XII is one down, so they grab TCU (or whoever).
So since the BIG XII is still good to go, the PAC-10 can't lure Colorado or the Texas Block of 4.
So the PAC-10 invites Utah and one other to make 12, and does not need to go further.
With the SEC, ACC, Big TEN, Big XII, and PAC-10 all at 12 teams, no one needs to go further, so no one does.
To answer the question - "No".