OK now I understand what you mean...
Well you know that music has its rules...one basic harmonic rule is that sequence octaves should be avoided.
At that specific point my left hand plays the octave Bb (do not call it A#, it's not the same and it's wrong). If I play Bb with the right hand too, I create a chord made up of 3 Bb, this is horrible, sounds bad and must be absolutely avoided (if you do this in the music academy, they send you home immediately...).
Using different instruments such problems quite do not exist, this is what I mean when I say that this is a piano arrangement and not a copy. It must fit the instrument and add something to the original.
Cheers,
Satin Beaus
P.S.: For further information I think it's better if you send a PM, I guess it could be boring to keep always this topic up, it interests only the few...