Lol what? I can't remember exactly but I think I went to 3/4/5 different cobblers and out of those Fifth Avenue were the only decent ones.
I might've had bad luck or not done my research enough, but that was my experience. Of course there's good cobblers in London, I don't think anyone doubts that
The only decent cobbler I went to in London was Fifth Avenue Shoe Repair, but their service / attitude is horrible.
Perhaps check with https://www.trunkclothiers.com/ and see who they recommend? Or if they can handle it for you?