I'm going to see if I can get that fixed in a bug test as another user was reporting it. I think something caused a variable to get out of sequence with the debug room.
The NPC you were seeing was to trigger the Khrono Tomb's boss defeated which I think is causing some issues. I forgot they were standing there still in this build vs hiding some of the other debug stuff, oops!
Thanks for the report and sorry for the spooky!