I think you are doing a GREAT job and Goldie and her flock mates are lucky to have you.
If you don't have a poultry vet I wouldn't recommend a vet that doesn't see chickens as you typically know more about chickens than they do sadly.
She may have a bit of fluid in the lungs if it is still respiratory and will take time for her body to absorb. My vet typically prescribes antibiotics which I believe the treatment you are providing in her water is that correct?
Keep up the treatment and keep an eye on her, my husband and I like to let them be chickens as much as possible and only interfere when they would be worse in the situation they are in.
If she is with her flock foraging and eating, drinking and pooping normally I would say you are doing all you can for her.
Keep up the great work; I am sure you will get more people to chime in here to help Goldie further