In addition to naming a character Romero after George A. Romero, this character's first name is Martin. "Martin" is an earlier George A. Romero film.
The sect's first victim is named "Marion Crane", a reference to the main character from Psycho (1960) that was played by Janet Leigh, the mother of lead actress Kelly Curtis.
The opening scene states the year is 1970 but the song playing is America's "A Horse with No Name" which came out in 1972.
"Zombie Flesh Eaters 3" (1989) was shot in Rome on sets borrowed from "The Sect."
Romero was named after 'Romero, George A.', who writer/producer Dario Argento had just co-directed Two Evil Eyes (1990) with.