Unfortunately, Blizzard doesn’t have any sort of strategy in place to rethink a decision. Once they rule on something they are very very slow at changing their mind if at all.
I’ve been here and done that. I ended up losing my game cause they assumed something that wasn’t true - which forced me to re-buy the game. Win win for them.
If, indeed, this ban is due to a controller use then I suspect it’s because they want you to purchase their controller. Essentially pulling a Microsoft tactic as they did with their browser some time ago.
I wish you well and hope that you are able to get their attention as unlikely as that may be! They aren’t very good at any sort of communications. It takes them a long time to address anything!
I know you and enjoy playing with you (although haven’t lately!)