Mason Farm and Ranch
Songster
Side bar:Does she have any lice or mites?
The crop should be checked first thing before she's had anything to eat/drink, it should be empty/flat.
With the intermittent foam in the eyes...shaking head...
Eye worms?
You're upper faculty level in chicken matters, are you still convinced this is MG? I'm not. But I've never seen a confirmed case of eye worm.
She's definitely got multiple issues going on. I'm thinking a parasitic is definitely in order, but which one? Most can't be mixed and none treat everything.