I just found a connection to 3 more accounts so I suggest everyone look deeper into this too. There are most likely more accounts connected.
If you are going to use posts from a long time ago as evidence of a connection, then you need to account for the possibility that an account has been sold since a post was made. In order to rule out this possibility, you should get the archives of the security log to check for password changes, and use good judgment to consider if an account was sold or not.
I'll just post the connection that I find and if the account is sold it's not really my fight to fight. It's the person who bought the account.
It would help if you let us know if you sold any of these accounts in the past.
We can't really trust the alt known as quickseller's word on any transaction as s/he could just pick random names of UID's as the recipient and we'd never know and then quickseller would just keep on scamming.
A new owner of a UID might not be a scammer, but it's like the analogy of a car - a person might not have been behind the steering wheel when it deliberately ran the red light, struck and injured multiple pedestrians before colliding with another car and killed that car's occupants, but the car itself was involved in the accident.
And so it is with UID's - The UID was involved in the scam, took the money, fiat and or BitCoins or other alt coins and so I
Red Paint TM the UID for the very reason it was involved in the scam.