But why is it not on the regualt Zoyi site?
Even the domain registration info for szzotek is odd.
It's behind a private registry service, just like the western zotektools.com site, just a different one. That by itself isn't that uncommon (most of my domains are behind private registrars), although I would expect most legitimate businesses to expose their domain contacts. I was skeptical of szzotek too when it was first mentioned (pretty sure in this thread) and suggested caution, but did some digging and came to conclusion it was legitimately their China-facing site. If you answer the prompt about English, it actually redirects you to the zotektools site.
Many Chinese equipment manufacturers have different internally-facing sites. Also some of them (e.g. Rigol) will post firmware updates to some sites and not others. So this really isn't that unusual.
On a loosely related note, Darren Walker had a Zotek rep on his YT channel a week or so ago when he was unboxing the 703S and asked her about the Zoyi vs Zotek distinction. We all knew they were the same company, but she clarified that Zotek is the western facing brand while Zoyi is the internal to China/Asia brand. She said they weren't allowed to market as Zoyi outside of China, so adopted the name Zotek. She didn't explain why, I assume for trademark or other reasons.