He gives Clausen a shot and the organization finds out of he can play or not. If he can and he plays well even if his stat line isn't great they can promote Davidson, and either promote Scherer (QB coach) or another guy from that NE offense tree.
Clausen sucks terribly gut everyone not on the defensive side of the ball and use the first round pick next year (likely a top 10 anyway) to draft whomever the hell they want at QB. The offensive line has talent even if they haven't done well without Otah as yet and a good set of running backs anyway.
Carolina if nothing else has talent on both sides of the ball and solid pieces to build around so if all else fails they can bring in someone who only has to put it together and find that QB and it's ok, if that QB is on the roster then might as well find out now in a season that's already tanking.