They probably took real inputs and served their owned model to the user, while also getting the response from Claude to compare/train
It is not simple like that, anthropic claimed that they (Chinese labs) routed the api calls to Claude models to keep the illusion that Chinese models are also capable.
So it is not that the labs call the requests parallely and only return the internal version, but also serve those requests live so they can trick the users that the Chinese models are also great.
Which is very silly considering Chinese models are published to huggingface for everyone to test.