Not sure about the Hampton, but other CR models use aluminum studs for the slide-outs. There is no OSB in the sidewalls, just fiberglas insulation. Also, the end walls used to have filon skins just like the other exterior walls and therefore lauan plywood underneath. But CR changed to a different type of plastic w/o plywood (again, not sure about the 2011 Hampton, but that is how my Cruiser slide-outs are built). Slide-out floors are made of a type of OSB, that is because they are a single piece and longer than 8 ft.
If the end wall siding is fairly flexible, then you probably have the plastic skins and not filon skins, in which case, there is nothing to absorb water and swell up, except for the interior lauan skin. So, if you don't see any issue on the inside, then you may not have a problem. If you have windows in the end walls, they might leak, so check them carefully. But again if there is moisture in the walls, it should be more evident on the inside.
On edit; it sounds like you have aluminum siding, in which case, there is lauan plywood underneath to support the siding. However, the siding is usually attached only where studs are located, and on those short walls they will be either side of the window. So, how much flex there is depends on proximity to a stud. Regardless, if there is a leakage problem, it should be obvious on the inside.
Edited by: Dayle1
Texas Baptist Men-Retiree Builders member since '01
13 Silverado 3500HD D/A, 2wd CCSB srw, custom RKI bed
11 Cruiser CF32MK