The way I see it, Washington has no incentive to even show up next week. A win and they potentially drop a few slots in the draft, which is huge. A win and they possibly lose out on one of the top two QBs or the best WR in Harrison Jr. Yeah, it is a division game. But business is business. The Washington players may want to stick it to the Cowboys but they would be sticking it to their future also. I highly doubt the ownership of Washington wants a victory. If I were the owner, I would make it clear (hint hint, wink wink) to the players that I want that 2nd pick.
If the roles were reversed, I would not want the Cowboys to win a meaningless game and lose out on the 2nd pick in the draft.