How to handle a ex that's EGO has been crushed?

I have a friend named Karen she recently just got divorced from a man that was not only narcissistic,abusive an a pathological lair! When she left him he was angry he started spreading nasty rumors about her saying she slept with over 50 guys! And she has a lot of STD'S! My Friend Karen is in her 30'she is 60 and he always say how he is the best at everything and can have any women! Now he is also a Guidance councilor at an ELEMENTRY SCHOOL! Should he be acting this way Should my friend call the school and let them know who they really hired? Oh and before they got married he was her social worker!