the super-high price is only useful once money changes hands.

This is a very important point. It is only one of the problems with the actual fulfillment of a "short squeeze."

What's to stop MegaCorp from 'sacrificing' a subsidiary or two to absolve themselves of the liability?

Legally speaking, there is likely a chain of liability. Corporations are designed to hide behind. They allow people to do all manner of immoral and illegal shit through their company, and then absolve themselves from personal responsibility by blaming the company itself for the actions; however, if you own enough stock in a company, there is a legal responsibility. Megacorp shows that there is a single owner for everything (although it doesn't yet name the people who own that single entity), and that that single owner has more than enough stock in the culprits doing the short selling to be legally responsible for its actions.

Having said that, that doesn't mean that it would play out that way in court. Megacorp shows the ownership, and to some extent the laws (more on that is coming in future parts), but it doesn't really make a case that will win in court (though it could be a valuable piece of evidence in such a case). A future part is designed to be a court case, not for MOASS specifically, but for the real problem (The Fed/BIS/All of Banking).

As I understand it, there were (in most cases) no stocks borrowed.

There were many stocks borrowed that were not actual stocks (as in, stocks offered for sale to the public by the company), but legally speaking these phantom stocks are still owed back by the borrower. They must be paid for when the short sale is due, even though they don't exist. Again, that's the law, that's not necessarily what happens. They have been, by fuckery, extending that time for repayment far past their due date, by short selling more phantom stocks to replace the ones that were due.

What is the 'guarantee' that the 'to the moon' prices will ever actually be paid out?

There is no guarantee. This could go on forever. They could renege on their obligations. They could do as you said, and find a way to absolve themselves of ownership and patsy away a few of their corps. But legally speaking, I don't think they can do that. Practically speaking I don't think they can either, because if they could, they already would have.

On the other hand, they may be waiting to play that card because there might be advantages to delaying the inevitable. Remember, they are the designers of The Great Reset. They want the economy to be completely destroyed. They may use MOASS for that purpose. If there is a MOASS, it could be the end of everything.

What is certain is, GME is putting a lot of pressure into the system, and it is teaching people about reality. The pressure is going to cause an explosion at some point, the question is, will we be prepared when it does?

Teaching people what the real problem is, along with the necessary preparations (solutions) is what the next couple parts of my report will show. The solution is the same no matter how the GME situation resolves.