Whether or not glue/sealant is a good idea or not I will leave to others to discuss.
But Gorilla glue is polyurethane. It is not UV resistant. Just like the spray foam cans of the same stuff (if you ever have gotten gorilla glue wet you’ve seen it foam just like the can foam), it will deteriorate exposed to the sun over time. Not sure about the glue, but the foams seem to last a few years, at least here in my climate. Breaking down in the sun may not be a bad thing either as far as grafts or a pruning sealant go, in that it will eventually flake off.