I don't accept that it was staged to look like an esoteric ritual event, IMO the sheriff just read that into the crime scene himself. The dead giveaway is his statement that the murder took place a few days before a blue moon. That's classic Satanic Panic fallacy - find a date on or around the date of a murder, attach some supposed occult significance to it, and hey presto its a ritual murder. Of course you can apply that fallacy to every date in the calendar, and therefore to any murder.
In reality, blue moons have no significance to Wiccans or Satanists or any other branch of the occult I've ever heard of. And although some Wiccan rituals are connected to the full moon, even those have to be done on the day of the full moon itself and not three days before.