Oh, I'm so sorry this is happening to you. It's unclear to me if she is offering to ship you an additional dozen eggs for free, or expects you to pay shipping and her material cost.
I was to pay shipping/mailing costs. I opted for a $5 refund instead of the 2+ dozen eggs. I told her that I could see we'd have the same shipping issues. I didn't say it was because she wouldn't reconsider her packing methods...