Please clarify
When you said he tested the switch, which switch are you referring to?
Are you talking about the break switch located under the dash connected to the break pedal?
Another question, when you turn on the running lights, do the tail lights turn on?
The under the hood fuse cluster should be labeled with which fuses go to what. I'm at work right now, but I'll try to find this out for you since no one else responded.
Also, I recommend that you guys get a multimeter so that you can verify that the previous owner didn't botch some of the wires.