It's hard to tell without more pics but if it were me, I think I would consider pulling the luan off the wall on the inside to try and see what's going on. It looks like the luan on the nose of the TT was installed after the sides. Not sure what the wall looks like around the bed and if you can peel it off down to the floor? If not, maybe you could cut the luan and put a piece of trim back on to cover the joint. Luan can be cut in a nice clean line by using a utility knife with a fresh blade and it's only stapled on with very light gauge staples which pull out relatively easily.