Hatching Some Eggs

So they were out in the yard with mom the entire time. Until they were having trouble hatching. They are Muscovy ducks. She started sitting on them Jan 30. So really they are past hatch day. They pipped about 4 days ago. I read all of the hatching 101. My last clutch had no trouble at all. There was no blood when helping these guys and I did it very slowly. Letting them finish getting all the way out on their own. But my first clutch took them about 30 minutes to get out of the shell. These guys took over 24 hours. I kept their membrane damp with sterile water and a q tip. Slowly rolling back the membrane making sure there was no blood. The assisted hatch actually went just like I had read. I followed the instructions closely. They have seemed to perk up some after starting th sugar water. I am giving it to them vial a syringe by placing a tiny drop on the tip of their beak. Being sure they only get a drop and it is clear from there nostrils. I am a vet tech and have an incubator that I use for puppies that I bottle feed. So I put them in there to keep them warm. I'm sure they are exhausted from trying to get out of the egg for so long. I also added a warm rice sock they. And be up against without being to hot but to simulate a momma duck. They are completely out of the eggs now and have defintently absorbed all the yoke. I'm pretty sure it was not an early hatch. More like a late hatch.