Leak in front wall

[creimer]

Hi: I have a 2015 Launch 24RLS. I notice the trim behind the mattress on the front wall was letting loose and there was signs of water leakage. The panel joint the trim was covering was uneven, with the top panel coming out about 0.5in. along much of that joint. There was some wetness along about 6in of that joint. I am assuming something has expanded with the water coming in. photos attached.

There was some cracking in the caulking on the outside on the joint between the rock guard and the upper part of the wall. fixing the leak won't be an issue but how do I go about opening the wall up a bit to let everything dry out? From the inside it appears the panel is glued on so will be tough to do without damaging the panel. I haven't looked into removing the outside panel. Any suggestions would be welcomed.