I feel your pain. I'm trying to learn how to over winter maples. Last year I had a couple tridents that didn't make it through the winter. I kept them outside with snow over the pots, but I think some bad winds got to them. That and I thought I could do some root work and repot them in their ragged state. Never popped a single bud, but they stayed green under the bark until the summer.
I had one trident purchase last year that I kept in a shed over the winter. I put it in a storage tote with snow in it. Didn't let it dry out. Buds look the same as last years dead trees, but I'm hoping it's a late bloomer. If not I think I'll give up on the tridents and concentrate on hardier species until I can afford a green house (yeah right!).