Yolk is absorbed in the final days of incubation and when hatchlings emerged out of their eggs the yolk is fully absorbed.
PATIENCE
I have hatchlings that have hatched a 5 weeks ago and have not taken a meal yet.
Not sure what you want to feed but this is what I do.
Offer rat first feeding some will take it some not.
Offer rat second and third feeding.
Offer mice to those that have refused rats previously.
Offer mice again to those that have refused the previous week
Offer mice in brown paper bag
Important things are to make sure the temps are not too hot, 6 quarts tubs do not allow much room to thermo regulate and I would consider providing temps of 88 on the warm side (not much hotter than that)
Have aspen bedding this allows them to burrow which means it allows them to feel more secure
Do not offer more than every 7 days.
Add crumble newspaper in the tubs of those that are hard to start.
Monitor their general look make sure they are well hydrated.
Note: I generally do not consider assisting before weeks 6 or 8 in most cases (that's an average).
It is base on overall look, health, weight, whether or not the animal absorbed it's yolk (in the case it did not it would be VERY different) etc.