Major embezzlement taking place in one of the divisions. Internal audit had completed a routine review of inte?

I would consider asking a neutral party that you could trust how you could approach this problem. Every company must be audited by an outside firm; you could contact them, the police (cooking the books amounts to fraud), the SEC, the IRS. Depending on results in these areas, and advice, I would plan my next move. From that point it might be out of my hands.