Hmm... My custom NPC greets the PC after killing them. How can I stop this?

I've tried various conditions in the hello dialogues. Nothing seems to help except a quest stage, and that's not the real anwer.

Since other NPCs don't do this ( I haven't noticed if they do ), and they don't have special conditions in their hello greets, I'm assuming I've missed something in the actor/NPC setup.