I am finding that the comb isn't a the best indicator for gender in this breed. My pullets have feathered out faster than the cockerels. Also the cockerels chest feathers tend to have a lot of white. Their being such a slow maturing breed makes them challenging to sex at a young age.
Are the chicks eating and drinking? If you are worried about them then take the other eggs. Otherwise I would assume that she has her reasons for not giving up quite yet. She may be able to feel them moving inside of their eggs. If I was not worried about the chicks that have already hatched...
Well it could be several things. Diarrhea can be a symptom of coccidiosis. Do you feed your chicks medicated feed or were they vaccinated for it? Ventilation is another big issue. If you do not have adequate ventilation you will have lots of respiratory issues. Have you checked them for...
Your hens seem to be good mama's at this point. I would trust them to care for the chicks and deal with any problems if they arise. As long as the mama's are accepted as part of the flock then their chicks should be as well.
The color of their combs is vital in telling gender at this age and the lighting in these photos does not allow for that. Number three looks like a cockerel in this photo. Also it helps to know what breed.
Was your chick sexed or strait run? D&B gets both but they get sexed chicks more often. At this age you can't tell what gender they are. Cockerels combs often start turning red by about 6 weeks where as pullets don't turn red until they are close to laying. Otherwise pullets have rounded...