I agree about how brazen he was. And how the girl’s mother had to basically solve the crime herself…I think it’s better now, but back before, say, the 90s, most missing teens were routinely dismissed as runaways (See my recent story on Dean Corll, for example).
As for why she published his stories…I listened to a podcast (True Murder: The Most Shocking Killers) where the host interviewed her. She had been “working” him to get him to confess, and one way she did that was to offer to help him publish his stories. She said her legal advice was that she should publish them, in the interest of the First Amendment. Plus, they were pretty good evidence of his guilt. I’ve gone back and forth with whether or not I want to read them; they sound pretty awful.