I'm a chicken novice at best... that being said, I did have a hen a few years ago that laid two lash eggs. She was a nasty little Red Sex Link named Plain Jane. Mean as dirt, but I loved her anyways. She laid a couple of those lash eggs (I had no idea what the heck they were til I looked here) and then stopped laying altogether. She didn't lay, but ultimately seemed in good spirits.
She got sick a few months after the last lash egg and I did what I could to make her comfortable in the house. Same sort of deal: pale, lethargic, just not herself. She had her own dog kennel to sleep in and I gave her Epsom salt baths on a daily basis for as long as she would tolerate it. Then I would sit her on my lap and towel dry her and we would watch The X-Files together. She ate boiled eggs and plain high protein Greek yogurt. Some days she would eat well, others she hardly ate.
During this time, she actually warmed up to me and started acting totally sweet and friendly. Kinda cool, really.
After a couple weeks of this, she really bounced back and appeared healthy. Back to the coop where she lived a few more months. One morning, I found her deceased in the coop. She acted normal up until the end so I like to think she went peacefully.
I know I don't have a lot of valuable input, but I thought I would share my experience with you.