The explanation for the brat's insistence that it was the sheriff who took her is that someone is pretending to be the sheriff, he can't even walk. I knew the kid lied, it was the way she said it, like she was gauging Abby's response to it. The killer won't let them leave the island, he's spent too much effort keeping them here.
The theory about the locals doesn't hold, it would have been cool if it did, it would have made it more clear who the killer's targeting.
Pity the sheriff's dead, I love Jim Beaver, and it was pretty harsh how he killed him. Wakefield really is alive but he's targeting Abby, the question is why? Wakefield's child is still out there, is that child working with Wakefield? It would explain how everyone more or less has alibis for the murders and why we haven't been able to narrow it down.