The gaming server and website is hosted outside the US. If the owner/operator lives within the US, he breach US law, if he accept customers from the US!
How about betonline and bodog? There are American citizens' sportsbooks and famous in fiat online gambling industry.
But the owners/operators do not live in the US and the US authorities can basically only act within the US, because illegal gambling is only a white colour crime. It would be something else if money laundering is involved.
It seems like no one has a clear answer on this, everyone is saying something different.. There has got to be some accurate guidelines available somewhere....
No, there are no guidelines and my info is accurate. You usually would need to pay a lawyer for accurate info, but as I go after criminal gambling operators, I know their structure.