US citzen working for gambling company?

Hi there i was hoping someone could help me with this, I have a friend that is a US citizen that currently works in the uk for a gambling company, He holds both a UK passport and still has his US citizenship, he and his wife both work for this company but they now would like to move back to where he is from in the united states. He asked me to post on here because he is having difficulty finding out if he would have problems continueing to work for this gambling company but working in the united states? I have had a little look myself and looked into the Unlawful Internet Gambling Enforcement Act which was passed in 2006 but that seems more geared towards stoping actual US customers from transfering and betting with online gambling companies. He just dosent want to upsticks and move to the US and continue to work for this company and then have the feds or something kick down the door and put him in jail.....any help, suggestions or websites any of you have would be greatly appreciated so i can pass it on to him, thank you all very much for your time.