I was on a government project where I found out I was being fraudulently billed on my hours

I was on a government project where I found out I was being fraudulently billed on my hours. It was towards the end of the year and my manager was trying to use up the budget of the client. Although this is normal in the private sector I told him from the beginning that you can't do this on a government project. The project was $1M+ which was enough for prison time. He had gone into our billing software and edited my entries - it wasn't as if he was submitting the fraudulent totals only - he was changing what I was entering. I gathered as much documentation as I cloud and went to a law firm. They told me I had two options - report it to the Government Accounting Office or report it to the head of the project, an academic. So I simultaneously resigned and reported it to the professor. I covered my butt. I'm pretty sure the professor hid the fraudulent billing but I didn't look into afterwards because basically that was what I was hoping he'd do so I wouldn't have to go to court and defend that my reported hours weren't really mine. …