If my husbands interview goes well and they stamp his passport can he leave usa got to egypt and bring his kids back for 2 month say and re enter with his stamped paaport or does he have to wait for green card? can his kids under 12 come on his passport?
He does not have to wait for card to travel. The stamp is the equivalent of the green card until he gets the card.
Bringing the kids here will be difficult. They will not want to allow them to visit temporarily, because they will think, that they want to stay forever and are just using the tourist visit to enter and then they will stay.
You can apply for the kids green cards and get them here in about a year.