First, you might want to explain to your husband that birds have to have grit in their systems to digest anything solid. So they shouldn't have apples. But they can have applesauce.
Right now, actually, applesauce (or apple meat put in the blender) would be a benefit if and only if it's completely pureed. The pectin will nourish good bacteria in the system and help cleanse the crop. But not much, please.
The majority of her food needs to be her pellets or crumbles. If she won't eat them straight, wet them. The yogurt is a keeper-continue to do that. You can also feed her boiled/mashed egg yolks (freeze what you don't use so your husband can spoil her while you're out) for rich nutrition. Mix the mashed egg yolk with a little water so it can easily dissolve.
Honestly, you can probably pick up any chicken upside down and get some stuff out of them like that. My concern is WHY she might have a static crop.
You'll want to pick her up and thoroughly and gently examine her. Check particularly for parasites against her skin, on her feather shafts, around her vent. Make sure there's no white or black waxy stuff on her vent and that it's clean and not terribly red.
That will rule out parasites which can cause a bird to be anemic.
Also, consider where she is and the heat. Some birds will go down in the summer heat. It's possible she could have had heat issues.
Check her weight - could it be possible that she's underweight because of being low on the pecking order? Is she able to walk normally or is she weak?
Remove her food at night and then check her crop first thing in the morning before replacing the food. A crop can feel mushy if it's filled with food, and birds are drinking a lot now because of the heat. But it should be mostly empty in the morning - not filled with mush.
In the morning before eating if it's still filled, then there's an issue. Especially if that continues for two days.
As for the acv water, are you using organic? You should be - regular ACV doesn't have the same effect other than pH. Organic still contains bacteria and its enzymatic action will help dissolve foods that are still in the system undigested. The bacteria will also help prevent a secondary fungal (yeast) infection from the statis of the crop.
let's hear how she is in the morning, particularly if the crop is empty, and go from there, yes?
