I see... a brown bear. A red bird. A yellow duck. A blue horse. A green frog. A purple cat. A white dog. A black sheep. And a goldfish looking at me. That's what I see.
So, hypothetically, if someone complained about getting an abusive PM from someone else, and the other person denies sending it, how could you get to the bottom of who was telling the truth?
(By the way, I hope you haven't had to deal with many disputes such as this).