I'm going to spare the angry comments about freezing your dragon into an excruciatingly painful death and try to help. I'm sure you loved Ziggy and were just confused.
I understand you may be new to dragons or animals in general and didn't know what to do, but like everyone said, 2 hours is not NEARLY long enough to get a response on here. Next time something like this happens, ask for opinions on here and then go to a vet, even if you can't pay, they will work out a payment plan to fit you I'm sure.
My dragon Ruki is brumating now. And even though she isn't
blackbearding, you can hardly see her breathe. One would think she's dead, but she's in a deep enough sleep where I can move her box around without her even opening an eye. I can sometimes move her over and she won't even blink. Just because it looks bad doesn't mean its unconscious. There may have been something wrong with Ziggy since he was
blackbearding, but only a necropsy could tell for sure, but I'm sure Ziggy is buried/disposed of already.
I would
seriously consider whether or not you can handle another dragon. I know that you didn't know what to do, but if you can put a living animal in a freezer so easily, then who's to say you won't do it again? I apologize for being rude, but it was extreeeemely inhumane and unconscious or not, he probably suffered a great deal before dying. I hope that if and when you get your next dragon that you read up A LOT more on what to do, like the proper UV lighting, feeders, etc. And if ANYTHING goes wrong, do not kill your dragon to put it out of its misery. There is NO good way to euthanize something yourself, leave it to professionals if you absolutely have to do it. Like I said, post to here for opinions and answers, and if it is an extreme emergency, go to the vet.