I don't know as I sat in the waiting room while they did it. They gave me the offending locking stud back and there's no sign of damage so I can only assume they managed to use the proper key. I suppose they must have used a ratchet gun and applied lots of pressure to stop it slipping off as it only took a couple of minutes. When I tried that with my DIY imact driver using the original key it sheared the shaped insert clean off.
