The incubation temp is too low for healthy growth. Get some fresh, fertile eggs to slip under the hen and let her do the hard work of incubation and raising.
That's your incubation temp? For proper development, temp needs to be at 37.2 to 37.7 for forced air or 38.3 to 38.8 for still air. Incubating at low temps can cause severe birth defects.
Chicken eggs only take 21 days to incubate. At 25 to 27 days, those eggs aren't hatching. Sorry, but they have been dead for a while now. And most broodies won't accept chicks until after they have been brooding for a few weeks.