Sour Crop - nothing is working

I have read so much conflicting information here I'm confused.

About 4 days ago my hen started acting "off" - when I examined her I found her crop to be swollen and squishy.
I do not feel any blockage. So I have assumed she has sour crop.
I massaged her daily, made her vomit a foul smelling brown liquid a few times.
I have given her yogurt, gentian violet, and yesterday started agrimycin 343.
She is eating very little (scrambled eggs, yogurt, soaked crumble) and I don't think passing much if anything. Losing weight fast.
My problem is I don't have a vet who will treat her. So I can't get nystatin. I live on an island. When I called him he told me there was nothing he could do. So frustrating!
I'm not sure what to do. Any advice is appreciated!