I believe I saw someone else post something in regards to the FOB not working and the dealer replaced it at not charge. IMO, it is part of the functionality of the vehicle, thus it should be covered under the bumper to bumper warranty.
Putting a FOB through a washing machine wouldn't be covered I'm sure. A lot of electronic manufacturers put in water sensor dots that change color when exposed to water on the inside of their products for exactly the reasons here...so that it wouldn't be covered by the warranty.