How do you know it wasn’t produced by them?
Someone in the FBI would have access to underground CPUSA documents.
It may have been. Feel free to provide evidence it was. Until then, it is simply a list produced by an anti-communist author and entered into the Congressional Record by a congressman at the request of a retired newspaper editor.
Neither I nor anybody else can prove the negative that it was NOT produced by the Communist Party. That’s why those who make assertions are required to provide evidence.