Honest answer? I don't know. But when my business was in a similar position (not from VCs and only about 25% of that amount), my business partner, attorney, and accountant sure did, so I know it can be done. IIRC, it was a fairly complex mix of different things. There certainly wasn't a single place that held all of the money.

I know that this sort of problem isn't new, and I know that there are a variety of ways to mitigate the risk to acceptable levels. I don't think you can ever completely eliminate risk.

Dealing with large amounts of money is very complex and really requires experts to do right. I'm an engineer, not a money expert. Your question is better aimed at a subject matter expert.

But my underlying point isn't even that these companies did the wrong thing. Only that they took a risk -- and starting a business is itself taking a risk. That's not necessarily a bad thing.

But when you take a risk, you're (obviously) taking a risk that the money will be lost. That's truly an unfortunate thing, but everyone knows the rules of the game.