I agree with keeping Decker in the mud room, at least for feeding. Raccoons have many terrible diseases that they carry but are asymptomatic, such as strep throat, giardia and roundworms. Raccoons can give diseases to dogs as well.
I agree. The raccoons pose a real threat to Decker, but most carriers I think of are too small for him to be able to drink water or go to the bathroom as needed throughout the night. Plus, I'm not sure what design of carrier you're talking about, but he may be at the mercy of the raccoons if he's confined. He would be much safer in your mud room.