@rommix0 I doubt so too, but it might be worth a try. My idea was based solely on the fact that Hebrew and Arabic have similar writing systems, in which vowels aren't written out in most texts. So synthesizers kind of have to guess at which vowel works where, and I figured BeST might just be taking the lazy approach and expecting you to write out the vowels.
I suspect something similar might be going on with Japanese, where Kanji are not being read out properly because they can actually have multiple correct pronunciations depending on context, where Hiragana and Katakana do spell out specific sounds so a synthesizer would have a much easier time trying to figure those out. The only thing that sustains that claim is that the word "konnichiwa" is read out properly and that one is usually spelled in Hiragana as far as I'm aware.
Of course, again, this is all speculation and I might be completely wrong, but I'd like to think my thoughts hold a little bit of water haha