Want to give a final update in case anyone else has this issue in the future. Disconnecting and reconnecting the thermocouple wires helped, a bit. Two firings failed at 250F, and a third at 500F. The thermocouple was new, and only had a handful of firings on it, but I replaced it anyway and that solved the problem. I've run two successful bisque fires in the last two days. So, a new thermocouple can fail and when your Skutt displays FAIL without an error code, it's the thermocouple as Cadenrank mentions above.
It's nice to be back in business.