Update: My vet called again, and we had a very long discussion about Cozzi. I asked all sorts of questions. I asked again about all of his blood tests. She said Cozzi's white blood cell count came back normal, but that still did not rule out that he could have an infection. I asked about his heart in the xrays also, she said she wasn't able to clearly see it because it was fuzzy/hazed out., but there was "loss of normal silhouette of his heart" giving her indication that he has possible heart disease. She said she could prescribe the nebulizer but wouldn't recommend it until after we see how he is after the 3 week treatment of the Virconizole, because she would have to switch his meds again. She said if after 3 weeks there is no improvement, she would revisit him and suggest doing a trachea swab & culture to see if he tests positive for a fungal infection, and what type. I have Cozzi getting lots of rest, that is what he wants the most, besides wanting me to snuggle with him. I keep the room dim, and turn them up fully when it's time to eat. He is eating well still. I just ask for lots of prayers for my little Cozzi. (nickname Cozzi Bear). Thanks everyone for all of your support.