RV Repair: Delamination, skylight dome, winnebago journey

Question
The outside fiberglass sidewall (behind my shower) has delaminated (2000 Winnebago Journey) - about two feet wide from floor to ceiling. It turns out there was a small leak in the seal around the skylight dome over the shower, which then ran down the outside wall. This may have been going on for some time. I talked to one body shop that said they'd probably have to cut out the fiberglass, dryout and/or replace any rotted wood on the interior and then reattach the outer wall - costing in the thousands.
My question - since the damage is behind my shower, would it be simpler to remove the one-piece shower, and then cut a "window" from the  inside - being careful not to cut through the outer fiberglass, and then dry the plywood surface by blowing air into the space with a vacuum cleaner exhaust? When all was dry, I'd apply adhesive to the two surfaces, replace the cutout and then push the fiberglass laminate against the now-dry wall. Then with the shower stall reinstalled, there'd be no visible seams on the exterior or interior.

Answer
In theory, that repair sounds good, however, it's not likely that your repair would hold.  This has been tried in the past, and works to a point, but depending on the amount of fiberglass delamination, usually can still see where it came loose.  The best repair is as the body shop suggested and if they are good at what they do, you will not see the repaired area.

   It all depends I guess on the amount of money you want to spend on this.

Garry