My understanding is they would play the games if it could effect seeding. Potentially worst case scenario would be braves and Mets win and dbacks lose which would eliminate them. In this scenario the Mets likely just don't try on Monday, lose game 1 and game 2 doesn't get played as all seeding is locked in at that point. I don't see them trying for the sweep, wearing out their players, just for the chance to move up 1 seed. Though we still face a Mets team we've dominated this year.