Neosporin is safe to use, especially on her ears, how can she lick the back of her ears LOL I use Neosporin when Charlie had an infection near his *ahem* man area, and it cleared it up within a few days. Of course I also had to make him wear a cone... theres a number of times when they've had little nicks or cuts or scratches where I've used neosporin and they've never got sick from it.

And IF she had mites, you still wouldn't see anything "alive" because mites are microscopic and can't be seen with the naked eye. But I'm sure if they WERE mites that it would have come back as positive for mites from the tests the vet did.