Thank you, what I was hoping to hear.
I generally got the impression that there are only few designs which many ‘brands’ share, whereas the only exception are Hohner and Suzuki (you won’t find a generic look alike).
At the above Ebay link, it doesn’t show the inside of the instrument, neither claiming to be identical to the Yamaha. But considering this video and the identical outside design, one must consider false-branding.
If you say that the sound and construction is inferior to the Yamaha (I must say that it doesn’t sound like that in the video), then this is the best info that I have.