It's what Jesus would do. I'm certain Jackson won't be taking the bout with Evans, now. He mentioned his jaw injury to Dana during the non-committal discussion after UFC 96 in the locker room. He wants to help Bisping train and then get his own camp in, so I don't expect to see him fighting before July.
Rampage kinda owes dana some loyalty after the whole incident he had last summer and how Dana stood by him. I can see Page feeling obligated to take on the fight to save the card. IMO Dana should just go with Lyoto vs Evans and come up with an injury for Rampage to not fight so soon. He can be ready by Sept-ish and the winner of Evans/Machida should be ready by then too. IMO the issue is I don't think Dana wants to see Machida with the belt because he's perceived as being a boring fighter and it'd be bad for the UFC to have a dull fighter as the champion of the most glamorous division