Suppose that I want to make a medical device, and I want to get liability insurance for when a bug in its code administers a lethal dose of radiation to a patient.

Is there any extant insurance company that would want to review my code in exchange for a lower premium?

If not, why would one be willing to do this for a flash-in-the-pan cryptocurrency, but not a useful, real-world device?

For an insurance policy like that, they wouldn't offer any policy without auditing the device, including the code.

Something like this: https://news.ycombinator.com/item?id=11789829