Question regarding used travel trailers

I've seen some both ways. Someone with the same trailer will have to give a definitive answer.

it almost seems to me like it is supposed to be that way because the whole side is like it. not like there are bubbles or anything and the material underneath is solid

but i want to make sure before i go further.

when you have a huge hole in the side of a camper that twists and flexes as it goes down the road, what could possibly go wrong?

Since 2008, some mfg's are hanging filon in smaller locations. The sheets are usually held in place by a tongue and groove section on top then molding holds the sides and bottom as it basically just hangs in place . They do not glue them . No delamination to occur.
However, they still can leak. A good way to tell , remove one of the screws at the bottom of the molding . That will be a low point in the design and water will collect there and drip out when you remove the screw.
Some people have been known to actually remove a screw at the bottom to allow a potential water leak , an avenue of escape.

The ends of my slideout are fiberglass with a Masonite type backing and have no additional backing. They appear to be glued to the actual wooden framework of the slide room

i checked with coachmen and they said that indeed the walls on the slide out on this trailer are not laminated or glued but just held in place on the outside.