My picks for most likely Regional hosts to lose, in no particular order.
Clemson: Auburn and Cal State Fullerton are both capable of beating Clemson.
Alabama: Central Arkansas will be coming in with a chip on their shoulder, and if Montana Fouts can't play, Alabama is in serious trouble.
Texas: Texas State has already beat Texas this year, and aTm is always a rival game.
Washington: The Huskies SOS is a bit low for a PAC 12 team. Minnesota is a strong Big 10 team and McNeese has beaten the Huskies this year.
LSU: Louisiana is always a rival match, plus the Cajuns will be coming in with a whole bag of chips on their shoulder after getting shafted by the SEleCtion Committee, and have beaten LSU in Baton Rouge this year.
Utah: Baylor will have a Frito-Lay truck full of chips on their shoulder, and when they are on, they are very, very good. Ole Miss is also capable of making some noise in this region.