the ATF has specifically directed them to report ......
AND THE BASIS FOR THIS ‘ORDER’ IS?......................
Threat at the very least of losing their SOT3 and their FFL and having their store shuttered, and at worst of being being sent to prison.
It's called the Chevron Rule, and it's the prevailing legal precedent. The Congress writes "open-ended" legislation and grants to the agency the power to sort out the fine details for themselves.
There is a case pending that SCOTUS has agreed to hear that will test Chevron. I forget who brought it but as best as I remember it wasn't anyone from the 2A/RKBA community. When listening to arguments as to whether they would hear the case, the Justices appeared to be divided right down party lines, 6-to-3 in favor of overturning.