Sorry to hear about your fishing buddy. Glad he's getting better.
We saw 2 snakes up Elkmont last week. One was for sure a garter snake about 18" long. The other we didn't get that close of a look at. My son sat on a rock to tie his boots and steped on the thing and it crawled back under the rock. It was under a bunch of leaves. Needless to say, he found a different rock. He said it was dark color. It was in the same area we saw the garter snake so I would reckon it was the same species, I hope...