Sounds like revisionist damage-control from the Sheriff to me... "I knew it all along, I just pretended I was dumb." Uh, yeah.
Their actions during that time period were consistent with what he said. I really doubt the Sheriff is a moron, and it was apparently pretty obvious to everyone who saw the first media interview that the parents were lying and the kids were nervous and confused about what they were supposed to say.
I don’t really know what he was doing, but I know it got my attention when he said soon after the event that they were very convinced from the family’s behavior (later thought to be acting) that it was not a hoax. At the time I said to myself, “Why doesn’t he just shut up and describe it as an ongoing investigation?”
So he is either stupid or clever, lol.