Thanks for sharing your experience. I don't expect to see any of the back-pay, but as this is blocking unemployment benefits it's currently costing me. I think I'll follow your example unless a new job is hard to come by.
Keep everything professional, and unemotional. Document facts.
Whether or not a new job is hard to come by, you are in a toxic situation, and if you are anything like me, your physical and mental health is already being affected.
Even if there is an offer of compromise by the CEO, I would be very suspicious given his past history.