"Prince tried to prevent publication of his legal name at one point"

"If I tell all my neighbors "X is a child molester!" and X did in fact spend time in prison for child molestation, then it is not libel/slander"

If X is not a child molester and you run your mouth about it then you could have serious problems on your hand. It's a good thing our system realizes that most people are stupid and will listen to anything "so and so" says.

x is a pig is obviously an insult.

If you shed someone in a bad light intentionally with statements that you knew were false then you have broken the law.

What happens if some idiot releases a porners real name?
They must be doing it for a reason. If the reason is to defemate them and they willingly use lies to do so then they have broken the law. If they did use true statments to broadcast news about them I don't see how they can get in trouble, unless it leads to stalking and the porner can prove that it was the result of the person's broadcast.
Are you a lawyer?