Cascading slicers as multiple tree selection

Hello everyone,

We have a dashboard with a slicer for cost centres. The sales organisation should cascade on this so that only the cost centres of the selected sales organisation are shown.

We have currently incorporated the cost centres as a drop-down slicer. However, this is not ideal, as there are several levels in the selection that are not easily visible to the user without the hierarchy being displayed. 

 
If I change the type of slicer to a multiple tree selection, the box (marked in red) where I can tick the cascade option disappears. Why is that? 

 

As always: thank you for your help!
Jona