When you and I sat in front of our monitors to see what others were doing, some people took inventory of their resources and offered whatever they could in the chance that it might be useful. They were willing for it to be thrown away if it wasn't useful.
I'm not here to apologise for Musk. I'm here to praise everyone who donated food, tanks, hoses, pumps, skeds, submarines, money, housing, or their life. Thank you.
I hope he takes that opportunity.
The main problem with the sub was that the rescue started earlier than expected, so there wasn't time to iterate. That isn't Musk's fault.
I wouldn't be surprised if the idea to use the stretcher arose after the sub idea was mentioned.
There's plenty to criticize Musk for (labor practices, hyping Autopilot recklessly), but it seems absurd to rewrite the events in Thailand in order to do so.
Given that experienced cave divers, including cave rescue divers, were involved with the rescue operation, saying that they needed Musk's sub idea to suggest use of a standard piece of rescue equipment is absurd and comes across as trying to steal credit.
The original intent of the rescue, judging from the Washington Post version of this article, was to have the two rescue drivers carry the kid between them as much as possible. It was realized when they were transporting the first kid that said transit mechanism was impossible, as the space was too cramped to do that; the operation then had one diver carrying the kid, swapping divers frequently because that's a very physically taxing job.
Between the weight and the length of the sub, it's clear from descriptions of the rescue operation that it was completely unusable. Any attempt to use it would have had a very high risk of it getting wedged somewhere in the cave that would have made the cave impassable. And guess what? Pretty much everyone who had some sort of experience with caving commented that the sub idea was unworkable when it was first announced.
Just because you want to help doesn't mean you can help, and you shouldn't give someone a pass on their actions just because they're trying to help. As the saying goes, the road to hell is paved with good intentions.