This possibly does happen. I wouldn't be surprised at all, but... I'd suspect it would simply be a easier to do overseas rather than contend with the controls that are in place.
What you can order on the clear web and have shipped via USPS (from overseas) is pretty telling already. The DEA intercepts perhaps 1% of those packages - so few that overseas pharmacies will re-ship if it happens.
Imagine what you can order via dark web using crypto - if it's not connected to you other than an address (which you could send it to any address and simply steal the package), the risk is minimal.
Bingo.
Fuck these rogue agencies. They are not the law. FDA has overstepped its authority since pretty much the start.
FDR voiced concerns about an organization like the FDA, explicitly stating they have no authority to dictate how medicine is used (only to ensure it's safe and not adulterated)... And yet here we are, with Scheduled drugs and lists of approved uses.