I don't think that an unknown Amazon employee going public could add much to the damage that the current media coverage has already inflicted. HR would probably just shrug it off. Also, taking a dispute with your employer public might cause other companies to think twice about hiring you in the future (your publicity will show up if they Google you). If you're down to your last alternative, it's probably time to find a new job.
It is hard to say. HN makes the development world pretty small. It is like a smaller provincial town where everyone kind of can find out stuff even if they don't know you personally. Damaging the image of a tech company on HN could be serious, it could impact ability to hire in the future.
But you are right, it is the nuclear option. After that even if problem is solved immediately, a stab in the back in the future is expected.
As for future employability, you are right as well. However, I can see a small start-up actually seeking out self-reliant people who have a sense of justice doing what is right. So the quality could also be appealing.
