There isn’t an embassy in LA. You must mean the consulate. Get a basic understanding of things and you’ll be better in the long run. It’s not rocket science. A delayed flight conflicting with your visa expiration is extremely poor planning on your part son. Or more likely a misunderstanding as any non O issued in October is still valid
I did my conversion from visa exempt to Non O based on retirement 45 days before my stamp expired. Another case where you make broad generalizations without understanding each office is different