I've never tried maternal incubation, but if I don't see them right away, then they start looking deflated like that, I'm pretty sure it is due to loosing water. I then put them in an incubator, but then really don't see them plump up more.
I have had eggs much worse than that hatch out though and be fine.
If they start turning colors, or leak, then they are likely bad, but I wait until it is VERY obvious before removing anything just to be sure.
Out of curiosity, what do you do if an egg is clearly bad, and is attached to the rest of the egg-pile? Can you safely remove it, and if so, how? I've heard they stick together pretty firmly.
Best of luck with your eggs!! I hope they do well for you!
Ball Pythons
1.0 Normal "Draccy"
0.2 Normal "Matika", "Lara Croft"
1.0 Lesser Cinny "Thor"