This was not the hooded robe dupe from around 2008 when hooded robes of umbra lost their tags and became neons (maybe they were just dyable) it didnt lose its tags so while it might be a related exploit, it wasnt a dupe of that exploit. most items like this are "legal" from what ive seen over the years and wont be deleted or anything. The last one that i saw sell was around 7 months ago. I think he sold it for 60 million or around there. I might be wrong and who knows maybe thats the one you bought. the economy has changed since then, so might technically be worth more, but you have to find someone who values it. Like my slime-dyed hat of the maji, rareity and utilization wise it technically is worth hundreds of millions, but i would have to find someone who wants it that much.
P.S. anyone want to buy a blue slime dyed hat of the maji?