As a followup, my mechanic was able to swap the coil on cylinder 2 (which was the one giving us the error code) with the coil on cyl 1. Bingo! Error code was now for cyl 1. Replaced the bad coil, engine now runs great. Tested the bad coil, tests fine. He said the bench test checks the primary circuit, the problem was in the secondary induction circuit. Greek to me, but it's fixed, so I'm not complaining.