Runner duck hatch
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You are right, it is usually best to wait.
Given your situation, though, I would be worried that some of them may be "shrink-wrapped" in the dry internal membranes, which makes it very hard for them to finish the hatch. If they were my eggs, I would take the one that has made the most progress, and carefully remove some of the shell around where the duckling has pipped. Then check the internal membranes to see if they are dry and stuck around the duckling. If they are, carefully peel them back, but don't break any blood vessels. Open up just enough to give the duckling room to move and then let him be for a while.
If the first one is shrink-wrapped, the others might be too. It happens when the humidity is too low at the end of the incubation. So, check the others for shrink-wrap.
Here is a good guide for assisting a hatch: