If Wisconsin or either of the Michigan teams win the whole thing, that decreases the at larges to 13.
And I've not run any predictor numbers to see what happens to OSU or PSU if any of the Michigan teams win Thursday- they are really close at this point, and a loss to either MSU or UM would be a pretty bad one this late.
Given that Wisconsin does have a bye, that situation helps them quite a bit.
Numerically, the worst thing for the B1G is if OSU and PSU both lose Thursday, and then anyone but Minnesota wins- that pushes both teams down and takes an at large spot- giving the conference just 2.
On the other hand, if OSU and PSU win enough to play each other Saturday, can anyone run the numbers to see if they climb enough to get 3 in?
Those seem like the only choices for the conference.