also, i wouldn't be surprised if the dog we saw was a ghost already, and hayden really did nuke him - don't really see what purpose it would serve though
Also - ben really needs to start putting some of these pieces together. He's really the only one in his family that has enough information to figure out that hayden's still a corpse, and she's haunting the fuck out of him. He watches the bitch get her face smashed in with a shovel, i guess he didn't witness the actual burial of the body, but both hayden and the burned dude give blatant clues to her current condition.
also - the exchange with hayden and burned guy in the basement has to mean burned guy is not a ghost.