I just went through something similar. I will preface by saying I am not good at culling. So that was not an option for me. I have never done it before and have always thought I would have nightmares forever if I were to cut a living thing's head off. However, I posted on here a couple days ago that I helped a bantam hatch (it clearly needed help) only to find out it could not walk. The toes were curled up and the legs were awkward to say the least. I posted and got a response saying that I could bandaid the straightened toes onto a piece of cardboard and leave it there for a day or two and the chick would be just fine. I tried this. The bandaid came off pretty quickly and I knew exactly when that happened because the chick stopped peeping loudly when it came off. I got a little more creative and tried to super glue the feet to the cardboard instead. I left the super glued 2cm x 2 cm piece of cardboard on the feet and gave it a little time. After peeping very loudly for a half hour straight and what seemed to be a significant amount of discomfort, I decided to cull. I cried and took a sharp pair of scissors to it and ended the suffering. Hopefully I don't have nightmares! This was an extremely hard decision but I think it was the right thing to do. I might suggest trying to bandaid the feet straight to some cardboard but it didn't work for me. I was really worried that it would get picked on by the others, and not be able to make it to the food or water easily. Whatever you decide, good luck!