like the same thing happened to me-same door!you should've seen my sons face when he did it-wow,just about sh#t his pants.
you'll need a long torx screwdriver and make sure you put loctite or something on the threads.the trick was to reassemble into opening while having handle pulled open,then put brown piece into aluminum slot and then push handle back down(at rest position).the screw goes into the door from theside.pull the weatherstrip a little bit to help.i hope you still have the screw
