think about it from the toyota poitn of view. they dont want you to ask for a new car. it would cost them WAY more than the small perks they are offering you. They will end up repairing the car anyway and selling it used to someone else. Assuming that you can get an independent expert say that if this repair were done, it would have no real degrading affect on the car, maybe counter them by asking them to do a full repair and much much more in a toyota GC. or all your services for up to 100k miles.