I would worm...
Why? The OP's description doesn't make me think immediately of worm trouble. Also, be careful, worming a sick bird is often too hard on the bird and can weaken them.
Is her crop actually emptying? You can tell by feeling it - withdraw food at night and feel to see if it is empty before feeding her again in the morning. If it isn't emptying, then it is impacted, which is a different scenario than sour crop (although they can both be going on at the same time, as well).
Sometimes a sour crop will also build up gas inside of it, which you can feel - it feels like a balloon with some air in it.
Amoxi - is that amoxicillin, an antibiotic? If it is sour crop, it could be bacterial or it could be fungal. If it is fungal, then giving an antibiotic will kill the good bacteria in the crop as well, leaving less beneficial microorganisms in the crop to compete with the fungus, so it can make things worse. Of course, if the sour crop is caused by bacteria, an antibiotic should help... but it's hard to know exactly what's going on inside that crop.
That's why probiotics, yogurt, and acv are often reccomended. They are all given to help restore balance to all of the microorganisms in the crop. I would hold off on the crumbles, and definitely hold off - WAY off - on the scratch. If she's having crop problems, they may be too much for her right now. After you're sure her crop situation is beginning to mend, you can move on onto soaking the crumbles in yogurt, and feeding that.
Just make sure she is digesting enough food to keep her strength up. I may have made the mistake, when I was fighting sour crop with my favorite rooster, of thinking he was eating and digesting more than he actually was. Sadly, he eventually died, after more than a week of intense nursing. I'll never know exactly why, but if I ever have to fight this again I am going to be really diligent about trying to make sure enough food is actually passing through that troubled crop.
Oh - and be careful about the 'vomiting'. Chickens can't actually vomit like we can, we can vomit and control whether we breath the vomit into our lungs, but if food backs up out of a chicken's crop, they have no way of closing off their airway and preventing themselves from aspirating it, which could lead to respiratory infection. So when you handle her, be careful about how you press on the crop...