Here is what it looks like:
Awww, Miss Olivia is so cute. I don't know how old she is. I would surely wait and see if it's an injury. My last hen did that and I was sure it was Marek's and it turned out to be a rare form of liver cancer. As long as she eats and keeps her weight, I would give her time. Stay positive. How old is she?
2 years old is possibly a bit old to have paralysis but anything is possible. Older chickens usually waste. Recently I had a wasting pullet and put her on antibiotics and sulfadimethoxine and she recovered. That is experimental-last ditch-lets try anything treatment. But you mentioning it reminded me of it.
As long as she eats, I would just stuff her with food. If she eats on her own, why tube feed her?
That's a large amount. I had 8-6 week old chicks that died one by one about 2 a week. It was devastating. I've had an 18 month old and a 2 year old get paralysis. They were both necropsied by a local vet, and he didn't see any tumors. I guess he either didn't look well enough, or they were in the nerves.
I guess I wonder if they really had Marek's unless you added more chickens to what you had. Marek's would have to come from somewhere, and usually someone with a nice same-age flock comes home with another chicken, and the trouble starts. I also wonder why you would have Marek's and not have any symptoms before point of lay.
Were the deaths ever confirmed by a pathologist and a necropsy? If not, you may want to look for other possible answers.