Can you send me a PM with the e-mail header? (Just scrub out your own/friends e-mail address by replacing it with <THISWASMYEMAIL> so I know).
I'll be able to tell you from the e-mail header if it is a hoax or not. The likelihood is that it is a hoax though. The e-mail looks like a hoax scam, and people who are really on the dark web doing illegal things have more important things to be doing like selling illegal drugs and stolen gift cards than trying to hoax people who are on the surface web (that is just how it is).
The chance of it not being a hoax is incredibly small. It is probably some moron in a poor country doing a mass-spam campaign to try and get people scared who will fall for it and pay the money.
Even if you check your Sent folder, it may still show up even if it is a hoax, there's a trick to spoofing that can cause services like Gmail to show the e-mail as having been sent from your own account, even though it wasn't.
I hope it's ok I respond to the thread, I also got the email, and can see that an email from my webmail account has been sent in the same timeframe (but no content in outgoing mail) there has not been sent mail from my smartphone or pc and I have have run a macscan without anything found:
Vendula Kubová can I send u a PM with the header?