Plot hole: The rule is Each buries his own as stated in the first movie. So Gus wouldn't have came back to life because he was buried by Drew and Jeff.
Pet Sematary II (1992)
1 plot hole
Directed by: Mary Lambert
Starring: Clancy Brown, Anthony Edwards, Edward Furlong, Jared Rushton
Revealing mistake: When the kids are burying Gus, his supposedly dead face flinches when they shovel dirt on him.
Gus Gilbert: You bury your own.
Trivia: Originally Stephen King's name was included with the opening credits; but after seeing a rough cut of the film, he hated it so much he demanded that his name by taken off the film, and all advertisements.