First, all allergies can be so specific to the individual that I'm not sure we can come up with a specific answer. That said, my daughter does have a mild to moderate peanut allergy. Enough for me to carry an epipen, but her episodes thus far have not required it. She has been seen by an allergist and had the allergy confirmed, but it's not as huge for us as it is for some.
I do not intentionally feed our chickies peanuts. But, their coop and half yard that is theirs to roam is below a pair of window bird feeders I have suctioned to my dining room window. One is a suet feeder that is normally stocked with a peanut suet. The other is a seed feeder that contains sunflower, peanut, and millet. I am sure my chooks get an occasional dropped peanut or suet chunk. My daughter has not had an issue with the eggs we get and we have made the choice to continue the feeders for the enjoyment of it.
I do not think it was a dumb question--anyone who has a child with an allergy like this knows how complicated it can be. In this case, I would consider the eggs to be safe after a week, but that's me. If she has the info, your friend can make her decision according to her comfort level. I do not believe the allergenic protein would persist in the chicken past a digestive cycle, as it can be processed out--peanut oil is actually non allergenic.