wow, sounds like a single GM must've take action against you but maybe didn't ban you...
Often the GMs have no proof of botting, but sometimes they will do stuff to you and you basically not saying anything makes it seem like you are admitting guilt, which MAY leave a tag on your account as a possible bot. I talked to a GM once about what they see in your history of dealing with GMs and they can look up all old tickets you've ever opened and the result of them, and notes of other GMs made on em, but the key thing was he said if you are accused of being a BOT by someone they only tag your account if evidence is found if this is true and then all future GMs can see it. But, if you have been accused and no evidence was found the flag is removed and future GMs have no idea.
I would say open a ticket to a GM and ask why the items were removed and say you bought em off neutral AH... I can't possibly see how they would have any evidence that you were botting unless they messaged you and you were afk whilst still doing this.