Northwestern winning is the best bet for the Big Ten to get three teams in the NYD6 bowls. I don't see how Ohio State beating #21 Northwestern improves their stock if Oklahoma avenges their only loss of the year by beating #14 Texas. It would take a lot of 59-0ish style points for the Buckeyes to leapfrog the Sooners, who have the better resume. Penn State is clearly behind Florida and LSU and won't be in the NYD6.
Cats win, and they get the Rose Bowl with 11-2 Ohio State and 10-2 Michigan near-locks for at-large bids in the Peach/Fiesta.