I think there is at least 1 mathematical possibility for ILL
ILL wins its last 2 games against Iowa, NW
Wisc loses its last 3 games against NW, Neb, Minn
Purdue loses its last 3 games against OSU, NW, Ind
Iowa loses to ILL and Neb, but beats Minn
Minn loses to Iowa and Ind but beats Wisc
If all that happens, ILL, Iowa, Minn finish in a 3-way tie for 1st. ILL would win the tie by going 2-0 against Minn and Iowa.