Thanks to all!
Now I managed to get it done, thanks to your advices and ideas.
I converted the Text into curves, made a copy of that group. Then I changed I took a guideline and changed the angle of the text. Then I placed the guideline where I want to have the cut and subtracted then with some rectangles letter for letter. Then I did that on the copied text group (and ungrouped them before doing the substracting). The OUTER SHADOW FX of the upper part (bigger piece of the text) is ok for creating the shadows on the lower piece. But that might look bad in case the text is going to be on background that isn't all black.
@ALFRED
Indeed English isn't my MUTTERSPRACHE, my fellow Designer from Scotland. Thanks for correcting my question. I had a sleep-deficit when I posted the thread. Insomnia does influence my cognitive abilities in a negative way, especially my verbal articulation and my writing skills. But it does boost my creativity, since it boost my Apophenia and Pareidolia, which comes handy when I use those "visuals" in a painting, design or drawing.