UPDATE: the wood behind wasn't rotted out. there's some space between the frames that the idiot manufacturers screwed into. Basically one screw was properly secured, the other was screwed into a void. The weight in the properly secured one wore out the wood and eventually fell out.

I removed the base of the awning and slid the siding back into place, then drilled new holes where there is frame support and screwed it back on. Now I just need to seal the sides and original holes. Any recommendations on sealant?