If the shell is zipped all the way around and the membrane is holding it together and turning white like it is drying out, I would help. A few snips of the membrane and chickie will probably be able to push its way on out. Membranes seem like they tend to dry out fairly easily here. I'm not a fan of helping too soon, but this little one may not be able to push the top off if the membrane is holding the shell still together and has dried out.
That was my fear as well, so I broke the dried strings of membrane and seconds later the chick was free and doing the chicky-flop, getting legs under itself and then resting. I added another wet cloth in a container and that boosted the humidity to 63%. Maybe that will help the rest. No new pips, the two last pips appear to have made progress, the second one does not.