Fraud can pierce the veil, so it's not just the company that they can go after, but also anyone responsible for the fraud.
... But where I am, bankruptcy only lasts 3 years + 1 day, after which point, those that had shares within the entity that has failed, or the part-owners, will be required to begin paying back their debts. Bankruptcy is not a failsafe to prevent you paying all debts. It's just a timeout to give you time to be in a position to pay those debts. And yes, it can be declared multiple times, but it won't always be accepted.
When such a company runs out of money, nobody else will be required to come up with cash to pay its debts. You don't need to read the bankruptcy laws to verify that, it's just the definition of a limited liability.
The USA having bankruptcy protections is what helps foster this level of risk and entrepreneurship here.
In this case, Xcor would need to pay back the fees they said would go to escrow. Not any investor who took equity on the gamble it would be worth something.
Certainly, if people were promised that there was money in escrow and it wasn't, that sounds like fraud, but that doesn't mean those who perpetuated the fraud have the money either.
I don't know the details of the situation but fraud happens all the time as well and without having more information, I wouldn't discount it as a possibility.
It's only fraud if they misrepresented the fact that it didn't yet exist, which seems very unlikely.
Buying things that don't yet exist happens all the time. Thousands of people put down deposits on Tesla Model 3's that did not then exist. People regularly buy houses under construction, and people often lose money when the contractor fails to deliver. It happens all the time.