We pulled the old 2-pin lemo cable after I had a look at the connectors. When I unscrewed the connector on the MC side, one of the wires came off. I suspect that it was still hanging on a bit, but my torquing it finally killed it.
We pulled the cable with the idea of resoldering the connectors, but there are at least 2 places where the cable has been squished enough that the shielding or the inner wires are exposed. These places aren't near enough the ends to just cut the cable short.
Downs doesn't have a spool of shielded twisted single-pair cable, so Todd is going to get me the part number for the cable they use, and I've asked Steve to order it tomorrow.
For now, we will continue using the BNC cable that we installed last night - I don't think it's worth resoldering and putting in a crappy 2-pin lemo cable that we'll just throw out in a week.