The pointer to the source of this claim is useful and informative.
The bigger the claim the bigger the scrutiny should be.
Whether true or not, Zenz's claim seems to be bought without question because it is useful for the current narrative against China, and this is not healthy. In fact it is counterproductive.
You're right, it is fascinating. I looked through the edit history and it seems like there's an ongoing effort to remove the references to his other beliefs. Among the referenced articles which have been scrubbed from his wiki: