Wish I'd seen your post before.
By eliminating surface moisture as a cause, you made the answer easy. You're almost certainly using a non-stick pan, too much oil, and/or moving the scallop in the pan before it's ready to move.
Preheat a pan (not non-stick) to very hot -- usually medium-high is right, but if your pan is large enough and your flame tight enough you might be able to go to full-bore (which will play havoc with the sides of your pan).
Pour a very little oil in the pan, and roll the pan so the oil evenly coats the bottom. You don't need more oil than will just coat.
Add the scallops to the pan, do not overcrowd.
Allow the scallops to cook until the edges just start to curl or show some browning, do not disturb them at all during this process. When you think they MAY be done, shake the pan assertively. If they do not come loose, they are not done. If they slide around, you may turn them. If they don't, allow them to cook another 30 seconds unmolested. Shake the pan again and immediately turn those that move. Count to 10 Mississippi before trying to loosen the stickers by pushing them with the side of your spatula. If that doesn't do it, you can go ahead and pry them loose.
Cook the second side very briefly -- you don't need color for presentation since it's going on the bottom, and you do not went to overcook the scallop. A good visual test is to check for a translucent line on the side of the scallop. If it's barely there, the scallop is a point. The usual press test applies. As soon as it pushes back, it's done.
Hope this helps,