Reading this narrative reminded me to a large degree of my own experience. I do not know what jurisdiction your friend lives in, but in mine, there are restrictions on live-ins being around during night time hours when the child is present. I would NEVER hire a counselor or psychologist without advice of Counsel. And I would certainly follow my Counsels recommendation on a plan of action to address any abuse. I am not familiar with family law, but it is my understanding that any allegation of sexual abuse of a child MUST be reported. Not reporting is an offense. Making a false report is an offense. Get with a good attorney an make a plan to address the problem. Dad is at fault if he does nothing and his child gets hurt.
Sorry, but grow a set and take action. Be prayerful. If CPS must do an investigation, keep witnesses and your attorney on call.
I asked him why he doesn’t trust CPS to do the right thing, but his experience says they don’t have the means to do the right thing. It’s less risky for them to come down on all sides equally, at least at the start.
I believe he’s getting a lawyer.