He knows that his crate is a safe spot. Still, the dog that wets is having issues. I assume that he doesn't actually need to go to the bathroom, right? Hazel pees in very specific areas in the house (it's why she's not allowed in without my direct supervision, she's got a bladder the size of a racehorse). She pees right at the entrance to my father-in-law's bedroom and my son's bedroom. All they ever do is pet her and play with her, and she does it within minutes of being allowed inside. This, for her, is clearly a dominance behavior because as far as she's concerned they haven't got a pack leader and we need one, so she'll step up to the plate.
It sounds like Moose is excited, but I think there's something more to it and I can't say with certainty without seeing it. Very passive dogs are more difficult for me to work with, probably because I do tend to naturally be dominant.
I would try a desensitization technique with him. Practice leaving and coming back. Start with very short periods of time at first, a few seconds if that's what it takes, and then come back. Do not greet him when you return, just pretend he isn't there. NO eye contact, not even a flicker, they see it instantly. Then keep extending the time you're "gone". That, along with calm, low voices when you greet him should be a good start. When he's in the mental state that you want, you reward that with attention. I prefer this to using negative reinforcement, especially with a dog who's got a history of possible abuse.
Hazel had the same problem, she'd been turned in twice and she STILL cowers at anything that resembles a stick. Even a paper towel tube. Fear-based aggression is easier to deal with than real dominance aggression for me, though it can be tough to work through the fear. But he's already got a pretty good start with you and your wife I think.
