> If you owe the bank $100 that's your problem. If you owe the bank $100 million, that's the bank's problem.
Crappy situation for OP and his startup, but I find the part about reading up on bankruptcy to be a bit premature.
Perhaps not the most ethical choice, but what stops OP from just not paying the bill, and finding a different cloud provider? Obviously they'll want to not repeat the "experiment", but seriously... there's no mechanism at Google to stop a new client from running up a near-$100k bill in a single day?
That's absurd, and should be a learning lesson for Google more than this startup. Some malicious actor could apparently consume hundreds of thousands of dollars of Google resources and "get away" with it.
Wait and see what happens, then deal with it - would be sane advice.