You should weigh the upside and downside. Upside is likely: you feel slightly vindicated, get a few up votes and comments when you xpost to HN. Downside is like

You should weigh the upside and downside. Upside is likely: you feel slightly vindicated, get a few up votes and comments when you xpost to HN. Downside is likely: burning bridges with that company, damaging your reputation by making people think you're stubborn and immature and will leak things that should be private. Best bet is just shrug it off and keep moving.