Blackmail works only if you don’t want people to find out. So, make sure that the general knows that everyone has “found out”. Then, there is no point in blackmailing him. He’s immune.
His formerly $122k pension, now $79k with the demotion will end up about $39K after his wife gets her fair share under the USPA when she tosses him.
I’m not convinced his was unknown by others over the past 11 years. Lots of blind eyes until the whistle was blown.