Unnoticed Shadow at Palomino Club

Re-watching Ghost Adventures and I noticed during the Palomino Club episode a black mass is caught on camera and seems to go unnoticed by the crew as it isn’t mentioned.

It happens at 31:57, a black shadow appears to cross over a mirror or doorway (can’t really tell) on the right-hand side next to the ATM machine. I have no idea if this was a crew member and if that’s why it went uncommented on, however to me it was very obvious and moved rather quickly (literally there for a slit second and gone). As far as I know Zak was the only one in that immediate area as Billy approaches him a minute or so later.

Did anyone else see this or have an explanation for it? Was it ever caught and commented on later by the crew?