Oh, what a sad story, I'm sorry but I don't have any advise but thought I had to post my best wishes for Dusty. I so hope this baby gets better soon.

Apart from the fact that this kitty is obviously very unwell, you mentioned that she had ear mites and that should of definately been picked up by the vet who saw her a couple of days beforehand. I don't want to worry you but this too me tells me that their vet probably isn't the best !!!

Fingers and paws crossed for Dusty, please get better and come home soon !!