DELAM

From your OP it sounds like water getting in through the screw holes. If you want to try to fix it from the outside I would remove the awning arms and probe the area underneath to see if just the screw holes (area around the screws) are rotted or if it extends into the delam area. If the rotted area is small less than 4in x 4in, you can fix this area with a mass casting resin such as Epocast or even Bondo. If you do a search on Gjac and delamination you will see the details of how to fix it. After the delamination is rebonded I would fix the rotted area by filling an empty tube of caulking with the mass casting resin and shooting it into one of the holes of the awning screw while blocking the other 3 holes. This repair is not for the faint of heart but if you are not afraid of a lot of work and mess you may be happy with the repair. Good Luck.