Just because it's possible to state a hypothetical financial product does not mean there's a useful product there.
Why would I agree to pay up to $20k on a $50k cloud bill, when you could just choose to spend more on your cloud bill. I would be giving away free money and you'd get a discount.
You have to tie it to either incorrect billing, valid billing but caused by a malicious third party (i.e. hacking), or valid billing caused by negligence, and in the latter case you would need to prove negligence otherwise it's just a business deciding to use more resources and not pay for them. In the same way, fire insurance covers your house burning down, but not if you burn it down yourself.
