Dear @satra @PeerHerholz,
I posted my problem as a new post here: How to use datasink to get BIDS styple output folders structure?.
And found the issue myself a few minutes after posting it. 
Dear @satra @PeerHerholz,
I posted my problem as a new post here: How to use datasink to get BIDS styple output folders structure?.
And found the issue myself a few minutes after posting it.
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