Smoke wouldn't help, but since the Tylosin didn't help, it could be a virus like Infectious Bronchitis, but without testing it would be hard to know.
Does she lay eggs? Are they normal?
Thanks for the video.
Yes, I would definitely make sure she's drinking the medicated water. If she doesn't seem to be drinking enough, I would syringe some into her a couple of times a day too.
The antibiotics can help treat symptoms of bacteria like disease like Mycoplasma and Infectious Coryza. Infectious Bronchitis and ILT are viruses but often a secondary infection may occur.
Hopefully the medication helps relieve her symptoms and you have no more problems...
It's probably too late to quarantine.
Since you started treatment, I would finish it. Tylosin will treat symptoms of disease like Mycoplasma. Your existing flock was not symptomatic correct?
Can you get a video of what she sounds like? Upload video to YouTube and provide a link.
Check inside her beak for canker or lesions and make sure her crop is emptying overnight.
She looks clear eyed and from what I can see there's no nasal discharge/mucous.
You mention you're treating...