I'm as fluffy a liberal as they come and yet... There is something about that bloke that makes the hairs on the back of my neck stand up.
Whether because he is a complete troll or because he is a sociopath I don't know but either way my reaction was pretty strong.
Personally I would suggest we meet in a neutral (but private) location. Take a friend with a mobile and hide him / her in a different room with instructions not to interfere but to call the police if worried.
And then tell him that dd has a new daddy now as I have a new husband and the three of us are a very happy family. I would explain what a wonderful man my new bloke is - how successful his career is, how well he supports us all, how much my dd loves him, how she understands that he isn't her biological father but she understands what makes a daddy and that is him. I might also muse about what a wonderful husband he is and how giving he is to me. (All to reassure Sam that "his" daughter is safe, well and happy of course.) There may even be a cheeky comment about how good new husband is in bed.
I would also explain to Sam how it wouldn't be in dd's best interests to know her "father" is a rapist and an abuser and any contact with him would not to be to her benefit and that I am sure he understands. Although I would definitely congratulate Sam on his "little job" as a security guard.
By which point hopefully Sam would have attacked me (violent triggers are definitely still there) and broken the odd bone, my friend would have called the police and I could wave him off cheerfully for another 5 years in prison.
And it would never occur to Sam that I did it on purpose as he has no idea what a pant would do for their child.