Unfortunately, I just followed the directions on the bottle of Gorilla
Glue that really do not emphasize the required clamping. It may have
some applications but as it seems tricky to use, I will avoid it. I
lalso wonder if it is really "waterproof" since I seem to be seeing it
give up on prolonged saturation.

W. Watt:
Your use of a light to spot voids is interesting.