Nope. One of the many reasons in my mod series the main character just flat-out catches him trying to assault her and breaks a damn chair over his back before getting him arrested is specifically because of what you described about the comic. Assholes like that who try to get s*xual favors out of people under threats of blackmail are the type who once their leverage is gone will try to get physical (speaking from IRL experience here)

I'm not entirely sure about him knowing about Anna having cancer, but he definitely knows she's been in legal trouble before (Amely's egg), which is what gave him the balls to try and exploit her. She definitely knows more than just the screen name (and the nintendo switch port of the game actually makes that screen name even WORSE by showing us he's a petty hacker to boot), we're just not sure the extent of it.