That's a nice little fantasy. In the real world, competent developers with that level of domain knowledge mostly don't exist at any price. In the healthcare field where I work, not many developers have ever gone to medical school.
You're telling me a software engineer could make a change that allowed spending money a company could not legally spend and he had no idea about it? Come on. That is preposterous. At any respectable company alarm bells would be going off everywhere and fingers would all start pointing to that change. Theres virtually 0 chance that there was not intent.