You can wait a bit longer or make a tiny pin hole just above where the beak is
If it’s been longer then 24 hours I do this and most times they still make the external and hatch themselves
I just like a peace of mind
I don’t make it big only a tiny hole the size of my tac pin
Grab a thick blanket and wrap the bator in it not covering the vent hold but should help to keep heat inside
Also running a shower on hot woth door closed will give you heat and humidity in case power goes out to long. Hopefully it doesn’t
I have assisted many ducks myself and have string healthy babies
But I would never force a hatch time start
The OP of this post has said these eggs have not started a hatch yet
No internal. No external
No bruises of wrong Position
These babies are not trying to hatch yet
What I’m wondering...
It won’t kill hatches to be higher or lower but it can speed up or delay them
Egg size and humidity also play a roll
If you have a smaller egg run high humidity you get a smaller air cell baby will fill the egg and hatch on time
With a lower humidity and smaller egg it will hatch early
Bigger...
Temp should be at 99.5 to hatch on time
98 is low enough this can cause the delay you are having
Please don’t start ti assist babies that aren’t ready yet
If your bator is off this can cause delays
Higher humidity means smaller air cells and babies can have ti much room and take extra time as well. Has the air cell dipped forward yet ?
I wouldn’t touch an egg that has not started to hatch on its own
Did you calibrate a thermometer and set it inside the bator at egg level ?
What temp and humidity did you run ?
What day did you set them and was it morning or evening ?