Except that she tells me "The blue cable's not in the timeclock." ... and THEN before I can tell her "Uh, did you try putting it back in." she says "And it has all kinds of wires sticking out."
Cue my 15 second pause while I recover from surprise.
How could this happen? Well, normally I'd say that a ravenous vacuum cleaner ate it, but these cables aren't on the floor - they're in little conduits underneath the desks on the trade floor. Doesn't go anywhere near a vacuum, and there isn't enough slack to have it even drape on the floor.
In addition, the piece of cable that connects into the back of the time clock is missing. About a foot of cable, gone.
Context also likes the copper thief theory.