Not a historian, but this thread might have the questions you're looking for: https://www.reddit.com/r/AskHistorians/comments/tnugs/has_there_ever_been_documented_evidence_of_anyone/

Short answer: no.

Longer answer:

Most pirates didn't have that much treasure to begin with as most of the pillaging was to ensure basic survival. The few pirates that did manage to get good money out of it would get that money out very fast on drinks and prostitutes with a small part going back to the familes on the main land.

As far as I know, only 1 pirate is known to have had some sort of secret treasure and that was Olivier Levasseur but this has never been confirmed.

Pirates like Blackbeard did have some money but still stole mostly to survive. The biggest attack for which Blackbeard is known is the attack on the port of Charleston in South Carolina just to get some basic medical supplies.

Sources: A hisotry of Pyrates, Spanish Gold + lots of reading on Wikipedia :p