Whether the Keeper is the blue badge holder does not matter. Anyone could be driving
My point was that in their appeal, which they have already submitted, the keeper (who is the owner of the blue badge) has already said that the owner of the blue badge was driving.
I agree that trying ASDA would be a wise first port of call.
Another point, in your opening post, you mention two parking charges, but refer to only one appeal. Each charge must be appealed separately.