I have seen this happen once before, I purchased an account that Arcus was the original owner of and hand't had access to in months. In the Arcus report, Arcus nor the person who had last bought it were able to recover it. I know the outcome was that the account information had been posted around too often and too many people had been on it for it to be recovered effortlessly.
Newports99 mentions he was on a twitch stream when this happened. I have took it upon myself to google the streamer and have come across that on his twitter page he has posted numerous times of him and possibly friends of his being locked/targeted by toxic people in the community. It has been mentioned that he two of the most expensive items in the game while on stream.
Proof of the streamer he was with has had personal account issues while streaming to his viewers:
Sick Nerd on Twitter
I don't know what else to say other than I'm not sure.