Problems hatching Silkies

We were trying to hatch our first batch of Silkies in a still air incubator and it has failed. We constantly maintained the temp, removed them from the turner at day 18 and kept the humidity high from then on. At day 21 we candled and noticed they were still alive so we placed them back in the incubator. Today was day 24 so I went ahead and pipped a couple and noticed the membrane was shrink wrapped around the fully developed chick and the chicks were no linger moving. I was down to the last 2 of 15 and they were both alive but their beaks were at the opposite end of the air cell and they were also develped. I started trying to help them by peeling back the shell hald way. They both appeared to be trying to push their way out so I left them to try and come out on their own but both have since died. Should I have pulled them out immediately or was there any other solutions to this? I dont see how it would have been possible for them to pip themselves out. They were so crammed inside. I'm so upset about it!!!!