My internet has been out for days and my phone service spotty, so I just got fully caught up.
My main reaction is
You put so much care and effort into these eggs, and you came so close to hatching! Hatching can be a very humbling experience, and its hard to know what exactly causes chicks to not hatch at the end. I wonder about genetics and inbreeding. My beautiful rooster has something wrong with his genetics that cause most of the eggs hatched from his daughters (I try not to think about chicken family relationships too hard, lol) to either not hatch, or be born with some weird birth defect. I've since stopped trying with those eggs.
I'm off to start my own high risk hatch experience, as I just put 15 shipped eggs in the incubator. I'm seeing evidence of old eggs (large air sacs) and detached air sacs. I'm hoping for a few to hatch, but not feeling terribly optimistic right now.