Your most powerful tool in negotiating with your employer is to threaten to resign. Even with COBRA, paying for your own health insurance can be a substantial burden for many people in the US. If resigning from your job poses substantial risks to your health and life, your employer holds all the cards.

A workforce that does not have mobility and security in the essentials of life creates negative externalities for society as a whole. If workers are unable to leave or report workplaces containing unethical or illegal behavior out of concern for their lives, that unethical or illegal behavior is tacitly rewarded with competitive advantage for the business.