Oh I'm so sorry, this is exactly why these damn Vets cannot just "guess" what is wrong with them and prescribe medications that aren't correct; Honestly the Baytril is them doing exactly the same thing, but I understand they are waiting for the culture results...I'm afraid she may have had Aspergilliosis this entire time, or a very bad Upper Respiratory Infection that is Fungal and not Bacterial, meaning that all of the antibiotics this Vet has given her has only made the fungal infection so much worse, to the point that it's all throughout her Respiratory system, lungs, Crop, GI Tract, etc.
****Do NOT put anything in her Drinking Water!!!!!!! The Qwiko powdered Probiotics are very good, but you should only sprinkle it on her food once a day, that's it. Please, if you've put any in her drinking water dump it out now, disinfect her drinking bowl with very hot water, and then give her fresh water, and never put any Probiotics, any medications, any supplements/vitamins, nothing ever in her drinking water! It contaminates her drinking water and starts fungal/bacterial growth in the water dish immediately, and she certainly cannot have that right now...So only on her food once a day...
****I think you need to speak to this Vet about Nebulizer treatments with the proper medication(s) based on the culture results... When an Upper Respiratory Infection gets this bad, or if it's something like Aspergilliosis or Psittacosis to the point that it's this bad, or a Fungi/Yeast, then the injections nor the oral meds are going to work quickly enough and she may die...Nebulizing the medication directly into her lungs and her respiratory tissue is the absolute best way to treat this at this point, and I'd almost insist upon it at this point. You can either build your own Nebulizer out of a large, plastic tub and a vaporizer, like the kind they sell for humans at drug stores and stores like Walmart, or you can usually just rent a proper Nebulizer directly from either the Vet or from a Home-Healthcare supply store...I made one using a plastic tub and a Vicks brand human Vaporizer that I bought at Walmart for $30. I had to do this for my Quaker a year ago, and it worked almost immediately. You simply dilute the antibiotic or anti-fungal medication, or both, in distilled water in the correct dilution ratio, which the Vet can give you, put it in the Vaporizer, put the Vaporizer inside of the plastic tub, put the bird inside of the tub, put the lid on, and let the bird breath the medication directly into their lungs and respiratory tissue for 15-20 minutes per treatment, once or twice a day...They typically show extreme improvement in the breathing symptoms after 1-2 treatments, and you continue them for at least a week or two. Nebulizer treatments are what most-all Certified Avian Vets are prescribing immediately now for birds with either a severe Upper Respiratory Infection, Aspergilliosis, Bacterial or Fungal Pneumonia, etc. They don't even mess around with oral meds or injections anymore. Treating a Respiratory or lung infection with oral meds is very ineffective, and injections aren't a whole lot better, as the medication needs to get directly into the respiratory and lung tissue...So I would be making this suggestion to this Vet ASAP, And if they tell you that Nebulization is not a good idea, I'd insist upon it, or insist that they have a phone-consult with a Certified Avian Vet immediately and ask their opinion, because I guarantee that they'll recommend Nebulization...