why the blue tarp over it? Does it leak somewhere? Could that be helping cause the "bubble", as in water damaged "wood" under there?
I don't know how old that R-POD is, but the newer ones don't have any wood in their construction. They use welded aluminum frames with the fiberglass exterior. I'd bet that one doesn't use any wood for the structure either. Just the floor and cabinets.
It does look like the roof has been leaking, but if no wood is in the walls it isn't going to damage it. I'm betting the roof could be sealed and the damage is just cosmetic. I bet it cleans up and is usable
