The monster suits in the Crystal Cove Haunted Museum include classic Scooby Doo, Where Are You! (1969) villains: Captain Cutler, Miner '49er, Charlie the Robot, Space Kook, The Phantom Shadow, and The Creeper. The Luna Ghost from the live action Scooby-Doo (2002) is also among them.
Matthew Lillard, who played Shaggy in the two theatrical Scooby-Doo movies, takes over his voice for the first time in an official capacity (he had previously voiced Shaggy unofficially in Operation Rich in Spirit (2005) and Ban on the Fun (2007)). The original Shaggy, Casey Kasem, provides the voice of Shaggy's father, which he had previously done on A Pup Named Scooby-Doo (1988).
Shaggy tells Velma he was watching a Vincent Van Ghoul movie last night. Vincent Van Ghoul was the character voiced by Vincent Price and visually modeled on him in the The 13 Ghosts of Scooby-Doo (1985) series.
One of the tourists in Velma's tour group resembles Don Knotts, who appeared alongside Scooby-Doo in Guess Who's Knott Coming to Dinner? (1972) (as himself), The Spooky Fog of Juneberry (1972) (as himself), and Scooby-Doo: Night of 100 Frights (2002) (as the Groundskeeper).