I know how hard it is when you are keen to make progress on things. Even when you post on here we may be at work or have other commitments and are unable to immediately respond. Please try to be patient, we will respond when available.
I would remove the panel AGAIN, take the front off AGAIN, remove the buttons AGAIN and carefully file or sand the high spots down, take your time do a little bit and recheck then continue until the high spots have blended into the rest of the panel. Emphasis on take your time and only remove the least amount of material from the highest points.
Buttons pop out with the panel off using gentle pressure from the rubber end of a pencil with the rubber in the end. By pushing from behind there are no marks on the face plate, buttons pop back in, plate back on and panel refitted to dash.