Unreachable glyph in Desert vault UPDATE: F2 from broken vault attached

(See screenshots)
This glyph appeared in a public run of the Desert vault from the Watch. I have not seen this happen before. Several of us tried approaching / moving around in front of and up to it from various angles, crouched, backwards, etc - the wall it's on is a full foundation thick, no access from the other side. Progress blocked, dead vault, had to leave. No interaction prompt ever appeared.