Actually I don't think that's delamination. I had to peel back the top front of my old Kiwi 17a which had an identical curved top. It's just aluminum over a wood frame. There really isn't anything under the curved part supporting it except on the very front by the bed edge. That part may have separated.
I think you're going to have to take off the molding on the top and pull out the aluminum panel until you can see everything inside. Let all dry out and put it back together. Then you might need to get clever and screw down some sort of flat molding on the warpage (though I do like your new word better) and seal it good. Trying of course to make it look like it belongs!
Take your time, and trust me, it's not as scary as it sounds. When you see how it's put together, you'll realize how easy it is to put back together.
2013 Jayco Jayfeather X20 E, 2008 GMC Sierra 1500 Crew Cab Z71 SLE