The name Hollow Creek Killer is a combination of the two serial killers from Criminal Minds: The Last Word (2006). One of the killers was called the Mill Creek Killer and the other was called Hollow Man.
In this episode they (FBI) (News Channels) refer to Louisville Police as "Louisville Police Department" or Louisville PD. In actuality the police in Louisville are referred to as LMPD or Louisville Metropolitan Police Department.
The trivia item below may give away important plot points.
The Hollow Creek Killer's M.O. of using a child to lure the children, killing them and burying them in lime is a reference to the Wineville Chicken coop murders in Mira Loma (then called Wineville), CA. In 1926, Gordon Stewert Northcott kidnapped and molested several young boys, eventually killing 4, burying three of the bodies on his Wineville ranch and leaving the fourth headless corpse by the side of a road. He was subsequently tried and hanged at San Quentin State Prison in 1930.