I would expect Michigan to double Epenesa, especially since it doesn't sound the rest of the DL is anything special. If Michigan can hold up well in pass protection, Patterson should be able to have a good game like he did against Rutgers. Michigan will still run it enough to keep the LBs honest.
Defensively it sounds like Michigan matches up rather well, too. Apparently Iowa's interior OL isn't that great either, which mitigates Michigan's lack of DT depth. Iowa's RBs are decent but not great, so I think the defense can contain that pretty well. I'm primarily concerned about giving up any big pass plays.
Otherwise, the biggest concern is turnovers. Obviously, Michigan has had some bad ones before last week and also hasn't really been able to force many this year.
It should be a close game. I'll say Michigan wins 27-23.