Unless Carpets are different from bps, half way is fine, from what I have seen from bp breeders (I used maternal incubation). Checking daily is enough air from my knowledge of the subject.

Hrm, all that seems about right. Other questions: Condensation in the tub? Mold? Uneven heating (unlikely, but thought I'd ask)? Nutritional deficit in the parents? Underweight mother (doesn't look like it, though)? Did you clip the eggs early?

Honestly I can't think of anything that would be a glaring issue here, I doubt it's misidentification and cross breeding of species...

Next time you could try keeping the eggs off the substrate (something I have seen a few breeders do) instead. I looked into maternal incubation with carpets and people have mixed success, many others seem dead set that artificial is the only way. Before preparing to breed again, perhaps take them to the vet for a checkup. And I was wrong on the temps, a lot of people have success at 87-88 degrees, so that wouldn't be a problem.