If he got an account, before he did, post in the help forums asking about it. be like -2 people i know on skype were banned along with their roommates just for sharing an IP address and my hubby wants to join and we don't want to be banned.-
show that you KNOW legit people who were banned and that your concerned. After he joins, make sure to add to your profile page bio thing "I share an IP Address with my Hubby (Username)
They don't ask people do 'let them know' but it seems those who DON'T do this tend to get banned. Their way of 'finding out who's cheating and who's not' SUCKS.