Trying to figure out if hen has mareks

[Cyan the chicken parent]

@azygous is it possible that the sudden roosting problem is old age? I never knew how old she was by the owner, I just have an idea by looking at her that now she is at least 2-3 years old minimum. She can also still see through the wonky eye, and it still dilates- is there a way to tell if it was an injury from that day? Or if the pupil is just a fluke? Do you know if mareks affects chickens over two years old?

 

[Cyan the chicken parent]

Update: We raised the pole in the isolation coop, to the height of the original roosting pole in their house (about two feet if not more)- and Flan made the jump! It might be that I gave her a higher dose of the vitamin B today! Maybe this was just a vitamin deficiency. I am still worried bout that eye though, any opinions?