Could be a "Stitches for Snitches" Move, the Problem in in every subject that involves a high amount of money. A bullet to the Head is a Message to Crypto.
He's not the first one to die for bitcoins.
https://www.thesun.co.uk/news/6215123/bitcoin-millionaire-pavel-makushin-russia-st-petersburg/the polish exchange ....yes very sad i also read this news some days ago.
But its now known if the shot his self or it was a mord.
regards
The authorities said that it's most likely a suicide but if the killer was smart he didn't leave any traces. When the police finds no signs of a struggle and the murder weapon in the victim's hand they usually call it a suicide and close the case.