If the Bills lose Sunday, I think there will be plenty of front office discussion about who to start at QB. In this scenario I think we will end up seeing EJ against the Raiders, with all sorts of Whaley-Marrone headlines leading up to the game.
At that point the needs of the organization (figuring out what you truly have in EJ) will be more important than a W. If Marrone fights that too hard, Whaley will see that Marrone is putting his need to improve his record above the org's needs. If Marrone fights too hard, he'll get the boot.