Question: Are open-throated Allison and the mutilated dark-haired guy near the end chasing Chelsey supposed to have become cenobites? Because they seem to be animated after death like the cenobites but they aren't wearing the usual leather gear and apart from their mutilations they look otherwise human.
Question: How did the box get out of the cement in part 3 and into a pillar in part 4?
Answer: Not sure why you submitted this question for the eighth film in the series. But regardless, that's just a bit of what's called "retroactive continuity," which is a term for when a movie either changes or ignores things from previous films. Rather than having the box be in the cement floor, it was relocated to a cement pillar. This change was presumably just because the writer or director thought it would look more dramatic for it to be ripped out of a pillar as opposed to being just dug up from the floor.
Answer: No they are not. They are just a figment of Chelsey's imagination as Lance Henrickson's character points out he put all of everything they saw in their mind, including Pinhead.
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