lcorin, what is it that he wants you to do or not do? What are you supposed to do for him, to prevent him from "turning you in" and sending those photos out? What's in it for him?
Unless you have seen what he claims to have. You have no way of knowing what he has. Or if he has anything. It is possible he has nothing. The person that told you they had seen the pictures and text could be lying to you. Anyone that is friends with this guy. Is not a friend of yours.
Are you out of that life now ? What does he want from you to not send the pictures and texts ?