I just wanted to provide an update and get some advice again

Hatch date was theoretically last Sunday, but I locked down early since I had had 101+ temps for a week. I had 3 hatch successfully early Saturday morning. 2 more late Saturday and a 3rd had pipped on Sunday morning. By Sunday evening the pip had not progressed, so since this was 36 hours after the 1st hatch I decided to help. I kept the egg on a heating pad with a warm moist towel and alternated that with my body heat and worked very slowly as the egg was peeping away. I was successful and the newest little fuzzbutt is running around with the rest. One of the early hatches had curled toes and weak legs. I was able to fix the curled toes with tape, which is now off, but its legs are still weak....meaning it rests a lot and is not as active as the others, but is moving around and eating and drinking.
I know we can't be sure, but were these hatch issues most likely due to the incy issues or that the eggs were shipped so early in the season....or more likely both? Out of 18 eggs only 6 hatched....and these eggs were expensive! So not sure I will try shipped eggs again. It is just really hard to find local eggs of any breed.
I'm thinking of opening the eggs to see how far they had progressed, but never having done that not sure it will give me any answers.