Most of the walls of a Bigfoot are fiberglass, glued to foam insulation/core, followed by 1/8" luan on the inside. This makes the "sandwich". Around the basement it is thicker plywood rather than foam. I've never been inside the front bulkhead, but if Bigfoot says it is plywood then it probably is.
The difference between this and boat construction is the use of contact cement. On a boat, the fiberglass would be directly laid up on the plywood (or foam), bonding to it with the resin. In some methods, the core is added after lamination using a wet bonding agent (like thickened resin). You will never see contact adhesive used for this purpose in a boat (well, perhaps a very, very cheaply built one).
The difficulty this creates when trying to fix delamination is that both surfaces (inside of fiberglass and surface of core) are covered with (failed) contact adhesive to which nothing will stick, except perhaps more contact adhesive. More contact adhesive will have solvents in it that may melt and reactivate the failed adhesive, or it may just make a mess. In a boat, the first attempt at repair is usually to inject epoxy into the void through small holes and clamp it together again. Epoxy will not stick to the adhesive in this case. The second attempt in a boat is to cut the delaminated skin off so the surfaces can be prepared, then either relaminate new glass, or bond the cut out piece back, then scarf the joint. That is a lot more work because of the finish work required. If the core is rotted due to water intrusion, then the core has to be removed to the edge of the rot and replaced with new.
if you have time, repairs of this sort aren't rocket science, the only hard part is the finish work to make it look new again. The bulkhead isn't that visible, so maybe a less than perfect job would be acceptable there.
I am surprised that you cannot get the door open on the jacks. For sure one thing that can happen is you can cross load the jacks, twisting the shell which will distort the door frame and bind the door. You can keep that from happening by watching the lower corner of the door carefully as you raise the jacks to keep the margin between door and frame the same on the side and bottom. The movement is fairly obvious.
