Just reading this now. So sorry. I also have an itchy dog; it really is a challenge. Thankfully he’s never had a bad ear problem. I clean his ears at least once a day with a towel (after drying him after a swim)—good for removing dirt and dust, there’s always brown stuff on the towel. Every now and then I do a thorough clean of the outer ear with an earbud and extra cotton wool, getting into all the grooves.
Have you ever gone the holistic vet route? Perhaps get advice on diet for an itchy dog? We feed Snowie raw meat and raw bones—we did this on advice from the breeder when I told her he was itchy. He’s still itchy, but at least manageable, no raw or bald spots. And no medication, except every now and then (usually when the seasons change) when we give him prednisone for a couple of days to give him relief.
I really feel for you. It’s distressing seeing our dogs miserable. Wishing you all a very speedy recovery.