Instead of replying to one of the schizos...
You are correct, an all-cash deal means the receiving party gets cash (i.e. not stocks, bonds or other securities, or equity in the resulting private company.) It does not mean the purchaser needs to have cash on hand.
In fact, it would be in Musk's interests to finance all or part of the purchase price, either solely or with a group of investors. Musk is dealing with Morgan Stanley on this purchase, who are more than able to solely underwrite a loan.
As far as the value of (Twitter) the underlying asset goes, Musk is an experienced entrepreneur who knows the value of leadership. I'd be surprised if he has not already assembled a team prepared to step in for current leadership, or has at least identified those people and would be working with a talent acquisition company to hire them. Facebook has been hemorrhaging top level staff, so there is a pretty wide field to choose from.
Musk has been clear about his desire to move off an ads-based revenue model and looks at the policy demands of advertisers as a negative. Last I heard, Twitter operates with about 300k daily active users, converting a portion of them into paying users isn't exactly rocket science. I'm betting one of the consequences of the ad-revenue model is acceptance of bot-nets from certain parties, and doing away with that would likely increase the subscriber base significantly.
My guess is his main risk is regulation, acquisition of the company and changes in policy would likely result in attention from Congress. While I'm certain this would be tough, he currently operates in more challenging constraints (self-driving cars have more complex regulatory requirements than anything short of nuclear power plants.) I'm guessing he's realistic about the nature of possible regulation and prepared to deal with it head-on.
But I would not look at this as a silver bullet for going after the people destroying civilization described in your message. Maybe more a way to get them focused on more constructive possibilities. The thing to remember about Musk is Tesla's mission is to hasten mankind's move off fossil fuels. He is ideologically driven himself, his ideology just happens to be more aligned with seeing value in the remarkable achievements of our culture.