I was just poking around my trunk, and thought of the brake light failure module.
I don't know how its wired, but if the current from the lamps passes though the failure module first, ( I observed three shunts in it, and it has power ratings on the box, so I'm guessing it does ) if the connection/module is bad I would think the lamps would not function properly.
Also, did you notice if the rear lamp failure light on the instrument panel was lit? I know when I had the box out of my car and had the key in the on position it was dark.
Good luck good sir