But who hijacked what account? Who is trying to get what guy banned? And who is well known?
Cliffhanger right there! 
While there might be no law, there is certainly the brand’s contracts with their suppliers and the chance that the product is better off flying under the FDA radar or not even legal to sell in the US. There’s a reason they print “not for sale on Amazon” on the bottle.
If multiple “pharmacists” are supplying the NSFE OP with products in violation of any distributor or supplier agreements with the brand, then the brand is likely already investigating the holes in their supply chain.
Hope OP isn’t selling those as “new,” either, but can you even sell “used” supplements? 