Well, this looks fantastic, doesn't it?! Not.
However it happened. It's bad - very bad - and it's like this on both sides.
My answer was Bondo. I blocked the inside with a piece of plastic and filled in the hole.
Bondo is an incredibly stable filler. If it works on vehicles in every climate, it'll work on the Teardrop.
Making a rain diverter is next. It will function like a gutter on the ends of the hatch hinge.
Did I hear someone pop a champagne bottle? I'll be right there...