Unsworth - who knew the cave system - said that Musk's idea was impractical and a PR stunt. Both of those claims are valid and came from a reliable source. During a crisis, there is no particular need to be polite to people getting in the way.
You can call each other names and fight.
Musk has gone beyond that and accused Vernon of being a pedophile and marrying child bride.
Maybe it was the heat of the moment. But then some days (or weeks) later he followed up with "I'd bet my signed dollar (that Vernon is a pedo)" (or something like that).
Musk intended to destroy Vernon with the pedophile accusation. There is no doubt of that. This is pre-meditated plan to destroy a person with the pedophile accusation.
For some reason, there's no outrage from tech companies though. People are still praising Musk as usual. I'm looking at you all the CEOs like Jack Dorsey and etc.
It is easy to see what is going on and that it isn't in good faith. Look a his breached commitments during the Flint water crisis (filter every home to below FDA levels), coronavius (produce ventilators), Peurto Rico huricane aftermath, and more. He as a common pattern with these kind of events.
And Vernon did not initiate the Twitter fight, he gave an interview and suggested Musk "stick his submarine where it hurts". Musk took to Twitter where he has millions of followers to strike back.
The tweets are deleted but somebody saved a screenshot: https://twitter.com/RickyReports/status/1018597245275557888?...