Which in all likelihood was the cause and they would be right! I'd be honest, while only saying what needs to be said. "The finish is peeling off the left vent housing." If asked what cleaners you've used, tell them. My service manager would likely instruct me on proper cleaning methods but still replace the "defective" part. I have found that, most often, honesty in such matters makes you feel good and has better results. Lies or BS are usually reciprocated. BTW I seldom use anything more than a slightly damp cloth to clean my dash. I will, on occasion, add a little mild dish soap. I frequently wipe my steering wheel especially if I've been overdoing the hand sanitizer!