This morning, we found that the whitish areas had grown up to be big ol' blisters. "Congratulations," I told my Gary friend. "You're now the proud owner of a second-degree burn."
Not to take away from the lovely dramatic climax that only a second-degree burn can provide, but the good news is that the burn looks like a minor second-degree burn and the electrical shock didn't travel across his heart, lungs, or even fully around the finger, so he should make a full recovery in a few days.
Also, Gary told me that his sister once got a plate-sized second-degree sunburn on her back, so she definitely wins.