If the company you bought it from wants to replace it, then I would say there is no remedy. Companies do not often 'give up' as it costs them money. I would be taking their offer or spend the rest of your days looking at the marks and feeling cheated.

Take the offer and enjoy a stain-free counter. You’ll be glad you did.

Rings next to a cooking appliance are evidence of a lack of trivet use. That also explains why the rings won't poultice out.

Were I replacing your tops for the second time, we'd be examining the slabs in the shop together and re-examining them at re-installation.