Recently quit my job due to retaliation from sexual harassment claim . should I explain to upper management why I'm leaving ?

I worked for a company for 10 years my third year in I was being sexually harassed by A peer . It became so bad that I had to report it ,it was investigated and proven true . HR asked me what I would like to see happen to this person , I explained that I did not want anyone to lose their job I just expect it to be spoken to in a professional respectful manner at all times .since then to avoid the retaliation I moved to a different department in the same company. A year and a half later I was offered promotion that was in the same building on the same team as the sexual harasser. He was moved up into management the manager that asked me to take the new job left the company and now the person who sexually harassed me was not my direct report but his best friend who was a female was who I reported to . I was denied a promotion to management because both of them refused to work with me . They forced another friend of theirs to apply for the position ,he did not want the position and was not qualified but they forced him saying that upper management suggested him when in fact upper management suggested I was most qualified. Do I expose the corruption , sue?