How do I report a named kill steal?

[bricke75]

I was camping Hadden since 5:50 AM this morning (CST). Around 10:45, Drest <Galaxy> shows up and sits behind me. He won't respond to my tells. Hadden spawns and Drest kills him while I am trying to cast/dot. He then claims he was there the entire time. Even though no one else was in the zone for hours.

He said his intention is to log in every 6 hours and get the kill. I have a screen shot.

How do I handle this?

Edit - Clarifying, there was lowbies in the zone off and on all morning, but only a handful of high level people passed through. A few stopped to chat (Netmusis and Pirahna <Aftermath>.