“Official” is still up to interpretation. The guitarist transcribing it is likely just deciding how he or she would most likely play the notes (or even how they sound) without doing exhaustive research into what was actually played. Syn’s style is a bit unorthodox, as his note choices are less linear than most guitar players. I mentioned in another thread that he played more like a piano player, and he said I was right about that.
I’ve bought a few of the A7X books over the years, and I always wind up going through some of the lead or melody parts with a pen to make them more palatable to my style, but I’m much less concerned with doing “exactly like Syn” and more about catching the notes and making it a little bit my own.