Well to me this sounds like you are allowing this so called friend do work under your company insurance as a sub contractor?? If so dumb move! Also if you know for sure he slipped back to his old ways you better do some fast talking to that HO. Even if this guy is self insured and he still slipped back to his old ways useing, you owe that customer a explanation of what you know and not sit back and allow this guy to do that job. Allow the customer a chance to make a decision of who he wants to do the job. You stated you make some money off this person? If so you owe it to them to be trustworthy in appretiation of their generosity as a PT customer. A POed customer will ruin you faster than a friend. More than friendship is riding here you owe it to your business before friends.