I am working to track and trace and time transactions and while this is possible when and if you know the identity of at least one participant it’s quite another thing when no identity is known at all. Criminals know that so it’s notoriously hard to pull off. Thanks to Daleware secrecy and lax Super PAC rules to disclose sources of funds it’s not going to get easier.
So either your friends are genius saucers or they have effective government intelligence that would be highly appreciated. I’d be interested.
You are spot on regarding the bedroom though. Exporting physical USD is far more lucrative, by the shipload, often by Chinese Money Laundering Organisations, for free.