A question I reviewed yesterday in Staging Ground that is inherently off-topic was close-voted by me and then by a moderator, which resulted in it being closed.
Today, I see a notification that it was submitted for re-evaluation after an edit, and a single, non-moderator user reopened it and approved it.
Concerns about that reviewer's decision to reopen and publish a still-off-topic question aside, this is clearly a bug. If a question becomes closed during Staging Ground it should probably be done, no longer reviewable.
At the very least, it should no longer be unilaterally reopenable and publishable if it was closed during review, since multiple users can't unilaterally reopen closed questions otherwise, dupehammer notwithstanding.