Chicken Being sick. Need some help

Hi, I have 11 ex battery hens and one has been sick. I've only noticed today that she doesn't want to go outside and just wants to sleep all day. Her comb is purple and her crop is full. She was sick when I went to pick her up and it was a brown liquid. I've looked at sour crop but I think it's a fungal infection as her crop feels like it has liquid in it. She will still eat and drink I just need some extra help. I've also seen that raw garlic and live yogurt will help if it is a fungal infection. I just hope it's not to late!