I don't like Keenum but I think Dalton at 32 makes for the 3rd best fall back option.
Id really need a stud young QB on deck if that scenario played out. The worst case scenario for me is parting with Dak and taking a clear step back. Everyone talks about how you can use that money to improve in other areas. I understand that, but believe there is a minimal competency a QB has to have in order for a team to succeed, regardless of other strengths. There are very few exceptions, maybe Trent Dilfer for example. We probably won't have a historically great defense though, and regardless of oline or running game strengths, I think the offense flounders with anything markedly less than Dak. Just my opinion, but if we'd made a move like that Id much prefer we went after an older not far removed from greatness type of qb and hope for a career resurgence with our surrounding talent. At least Id feel there's potential for that. Ill admit I may be selling Dalton short because hes ginger.
Edit - Id be interested in Carr or Cam as well. Also I know it would probably be a huge blunder, but I wonder if anyone will ever harness Winstons talent and reign him in.