I just rehomed our high school's FFA flock that was being totally neglected. I took two home myself. Sounds like both groups were in similarly horrible shape. The Golden Comet I brought home had an impacted crop and was about half the weight she should be. Both hens had bumblefoot, worm overloads, and bad lice infestations. Now the Golden Comet is dealing with persistent vent gleet. I've had them 3 weeks now. If I can get that vent problem cleared up (I'm starting medistatin tomorrow,), I'll begin integrating them next week.
The stress of the move stopped them from laying, but the Australorp lays daily. The Golden Comet was laying daily, until the vent gleet got worse. Maybe your girls just needed to settle in and get dome good food to get them back to laying condition. I'm just glad they're working out now!