I am sorry also you lost your job. Having known of a similar fraud situation in the past, and knowing the person who spoke with the FBI, they will try to keep your name private, but if it goes to court, you will become known I believe. This is my understanding. I also spoke with an FBI agent who specializes in HC fraud, she came to a chapter meeting, and she told me the same thing. I understand that to a point, but if you report them and follow the process thru, then your name becomes known. You would think most practices would appreciate your position, but there is the chance they will not see it in a good light. I certainly am not an expert, so you may want to check with a HC attorney who specializes in this area.
Good luck to you, I really wish you the best. And good for you for standing up for ethics!!!