BusaBrent,
Based on what you wrote about finding the one wire that you could move and get the tack to work, I would STRONGLY advise you not to cutting off the existing connector and then splicing a new one on. If you do that you will open yourself to TONS of potential problems down the road.
As was written above, the problem is most likely either a broken wire on the black wire, or even more likely it was crimped onto a portion of the insulation.
It seems highly unlikely that they can not get a pin to replace on that one wire. If that really is the case and your only option is in using a new harness, I would make them replace the whole harness with NO splicing anywhere in it. You have a lot of wires in that harness that are carrying variable loads and splicing can effect resistance and continuity, not to mention the potential corrosion problems.
