I get that if you are trying to keep your job, but when you quit and are on the way out why not at least alert the authorities to the illegal activity she was witness to? A letter to HR could have saved others the same treatment, if it was really that bad.Even after the fact alerting HR to issues is often career suicide. You may very bring down the harasser, but often yourself too.
But if alerting HR to illegal and unethical behavior by senior executives is career suicide and too much for you to stomach, then what is it called when you write a 1,000 word essay for Variety and throw the whole company under the bus? With a glamorous artsy head shot at the start of the article, just so everyone knows what you look like in addition to your name and full resume'? https://variety.com/2018/film/news/pixar-boys-club-john-lasseter-cassandra-smolcic-1202858982/
Is that also career suicide, or something else?