What do you mean the site "had a message"?

If there was some kind of message on the site against porn then it's highly unlikely that there
ever was any porn on the site or that anything illegal ever occurred and you were simply
tricked by anti porn zealots into confessing something you or your cousin never really did.

If you got some email message out of the blue accusing you of something you never did then
ignore it as a bluff. If something illegal really did happen then it would have been the police
contacting you and not some sleazy vigilante group.