Wouldn't go off my opinion though -What's the best suggestions for treatment? Or should I just suggest she go see a doctor?
Once you've removed the coating from the nail and it's exposed to air and been prepped, the pseudomonas bacteria has died. It is only the stain left behind that will need to grow out. Reapplying a coating is perfectly fine xDon't tell me off as I've not been in this situation (and hopefully won't). If someone came with a 'greenie' would you leave it until it grows out and not put anything else on the nail?