Nix is a chemical, and a nasty one at that. If vet recommended no chemicals, I wouldn't do the Nix yet. I would think that would sting in the burn. The drop of Dawn in the soaking water will help drown the mites, and give her some relief from the mites, until you can treat for them. Also, make sure she is properly quaranteened away from your established collection, so they hopefully don't get the mites.
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