The tagged can be viewed from two angles, first the user should prove it isn't a hacked account. Secondly, like every other user that have tried selling an account on the forum which is deem to be an untrustworthy act, he deserves a tagged.
As you can see from my explanation above, he tried covering up the evidence which means he was aware of the repercussion of sales of account. Now if i wasn't smart enough to archive the thread, i would had been the victim since I won't have been able to defend my feedback.
I haven't concluded, it say "possibility" right there on the thread's title. The tagged is simply a warning.
I'm leaning more towards the account being hacked rather than the user selling his own account with it, because most often than not people selling their accounts would just create a newbie account to post the availability of their main account so their "product" isn't being risked on having a red tag. Only a hacker would make this mistake by posting the availability of the account with a post on the account itself. There's really no sense for a sr. member really to make a mistake like this not unless the account questioned is owned by a new person beforehand.