and he wasn't just a diver- he was the recognized expert on the cave, having mapped it. He was also in close communication with the people organizing the rescue and was one of the few people who could say to Musk: "Thanks, but you're not helping"
I wonder why Richard Stanton, leader of the international rescue diving team, urged Musk to facilitate the construction of the vehicle as a back-up, in case flooding worsened. (Quoting from wiki here)
Because in an emergency, you sometimes don't have time, so you solicit options from many people, have them all work on their solutions in parallel, then choose the best one?
If you go back and look at Musk's tweets, it's pretty clear he didn't know what he was talking about it in terms of what would work.
