[Even if Lyle had noticed his eyes, he wouldn't have made assumptions. There were so many people here beyond "normal" that you stopped focusing on things that were only slightly off. If someone had a hand growing out of their forehead, that would have still gotten his attention. Someone's eyes? Not really]
I believe before the Blood Shack was established, we did have an issue with a vampire. However, I think it was more they were getting weak from not eating. I don't know what people do privately, but there hasn't been anyone asking any questions with regard to eating that I know of.
That's not to say vampires haven't attacked people. But we've had people who aren't vampires attack others too so it could be anyone.
It seems that you know a fair amount about vampires.