I have mentioned before that this is about the only way to get your account back to offer the guy some coin to give it back.
I doubt it will be the actual "hacker" you are dealing with. I think the hacker probably just sells them and then whoever actually bought the account is also screwed when it is outed.
I don't think it is unethical depending on how you feel about paying ransoms. In that case the "hacker" guy would probably be best off to demand a ransom for the account in the first place but this is more like an offer to return lost property.
I guess you could set up a specific escrow for this particular situation but what are you going to do for awareness? Offer your service to every "help account lost" thread?
So hacker gets account and sells it to a spammer (often plagiarist) and get paid, then the spammer that bought the account gets screwed when his bought account gets red trust but he can get $25 of his money back if he gives the account back. He might do it if he knows the deal is available.
Kinda dealing with some dirty folks.
it's probably better if more DTs will join the effort.
What do DTs have to do with it? It's just $25 but DT doesn't equal escrow..
You will just have to convince whatever DTs tagged it to remove them once the original owner gets them back..
It might make you look like you are running an account hacking racket though. If you are profiting off of it and have success it might look like you are the one getting the accounts to make a few bucks as a tagged hacked account is basically worthless other than this ransom you are thinking of.