If you take off the back of the cabinet in the front of the camper you'll see plywood ☹️ by where it connects..I believe the only wood in the trailer are the cabinets, if that helps. According to obi their floor is some sort of composite honeycomb.
Who installed sink for you ? When I installed sink in my 15, drilling through the floor for drain line, the flooring was this honeycomb thinga ma jigger material. Hopefully water damage to cabinets would be a minimum. The cabinets are plywood and much more solid then particle board etc....
The idiots at the rv place we got it from installed a new bathroom sink and they just didn't push the connections together enough. It wasn't an after market sink... just in the bathroom