Minny is fading. That leaves Illinois. If Iowa goes 10-8, that means they beat Illinois or number 1 Indiana. That would put Iowa squarely as the 6th Big Ten Team and having gone on a nice streak at the end of the season.
I really don't think the tournament committee is going to want to stop at 5 B10 teams if there is another team with an over .500 record in conference, particularly when the sixth team would have ended the season so strong, and with at least one pretty strong late season win.
Now, this is all in reference to the Iowa going 4-1 and not getting in argument. The only way I see that happening is if the Illini get hot and go 4-1, which would require them beating 2 out of 3 of UM, OSU, and Iowa all ON THE ROAD. If the Illini can do that, they deserve the bid hands down.
What do I think is most likely? Iowa and Illinois both end up at .500 in conference and the bid goes to whomever can win a second round game in the BTT. If neither can, Illinois has a chance, Iowa doesn't.