How can I tighten a loose screw in fiberglass side?

I've used broken off golf tees when the hold was too big for toothpicks to get adhesion.

My only issue with nutserts is that sometimes they can wind up spinning in their socket, making it impossible to insert or extract a screw or bolt. I've mitigated this with metal to metal connections by using a little bit of LocTite Red where the two areas contact, but for the screw to Filon, it may require using a nutsert and some epoxy so it stays in place.