In the spirit of other RE people, I've heard that you should always have three of the thing you're tearing apart. One to break, one to RE and one to have a known good to test against.
I also just wanted a few more devices to connect to the KX2-416 eventually anyway, so I'd ordered a couple more D2CIM-DVUSB's. I popped them open and...
Now, these two connectors look exactly like the connector they're using on the end of the board and here's the plug for that.
So now, I just need to figure out what kind of connector this is.