When I arrived at LHR T5 recently and a fellow passenger had a (normal, non branded) suitcase damaged (both wheels had been ripped off!) he was given an equivalent-sized new suitcase on the spot. Not involving K2 at all. They didn't do this to my Briggs & Riley though, nor would I accept.
Perhaps this is only possible at T5 at the heart of BA's operations, similar arrangement may not be available at outpost airports though.