It’s very sad that your tuner was destroyed. At least you weren’t!
On August 4, 2013, I activated Fairchild Mountain W0C/FR-010 in Rocky Mountain National Park. The peak is at 4115 M, 13502 feet, and the long hike required several hours. I started very early, but by the time I was setting up, clouds were beginning to form to the west, over the Never Summer Range - the same range where you were for your event!
I got on the air quickly, and despite hassles with a large marmot who tried to steal one of my guy lines, my CW activation started out great, with many chasers calling on 20M CW. After logging about 15 stations, I was still running a pretty good pile when I heard thunder. It wasn’t loud, so I stayed on - but in a few more minutes, I noticed that I was having trouble hearing some of the weaker chasers, because of a hissing sound in my receiver.
Within only another minute, all the chasers were covered by the increasing hissing noise! I heard another clap of thunder, closer, and I realized that the hissing was caused by corona discharge on the wire! Rain drops were falling on the rocks, as I jumped up and pulled the pole down. I packed up as fast as possible and began to descend. The immense summit of Fairchild is broad and exposed, and it was terrifying to be there as the storm approached closer, with the sky growing dark. I was lucky that there were no close bolts, and I made it down the slopes before the larger clouds and lightning bolts rolled in.
If you ever hear hissing on the air, it means that your antenna is already discharging significantly. Likewise, electrical tingling of the skin, hair standing on end, rocks hissing nearby, metal objects discharging - all effects I have experienced - these signs mean get off the summit ASAP!
Once a discharge begins, there is a chance that a bolt may follow along the ionized path.
My home-brew tuner was not damaged…