Everything worked very well as seen below. I waited 27 hours to remove the pressure, and it hardened as expected.
The bottom hole that was drilled yesterday was completely flush with the epoxy resin, so there will only be some light sanding to do there before painting.
The top hole needed some additional resin added, so I filled later on after the board was removed with Bondo. I've since caulked around the seams, including the suspected ingress around the screws of the fridge grate.
Very happy with how the procedure went, and glad I took the time to recaulk all around the camper this past week to make sure no other areas have this happen.
