Thank you so much for posting this and all the commenters too! I'm really sorry about your chicken.
We have a suffering hen with the same symptoms. I've tried the warm baths. I've administered 1 tsp Epsom salt in 1 ounce water (a one-time only medicine). I'm feeding yogurt mixed with oatmeal, oat bran and cornmeal. She is quarantined in an XLG crate inside the coop with the other birds. She has her own fresh water. ALL the same actions except she hasn't laid an egg since the development which was Friday.
(She's always been a daily layer. She's a leghorn.). She IS eating.
I saw that you finally had to cull her.
. I'm sorry to hear this. I've never had to do this and really don't know what/how to do it...humanely. Would you please tell me how you did it? Anyone have some advice for this??