SharePoint Document Library Grouping View

Hi.

In SharePoint Document Library, you can create views.  But sometimes those views dont go far enough.   I have a library with several columns that need groupings.....  This view for PowerBI has 8 main columns.....   I would like to create a view to:

Group by Business Type (Type A, Type B, Type C, Type D).    This is the Parent....

Then it has 5 columns that serve as children.   These columns group on same type per the column choices.... 

1.) Group By Department 1

2.) Group By Department 2

3.) Group By Department 3

4.) Group By Department 4

5.) Group By Department 5

Im trying to 1.) determine which PBI widget to use.  Maybe the table or the matrix.  but i would like a collaped arrow that user can click on to see all "like" items GROUPED pending which column chosen (Parent or one of the children).   Can someone tell me how to do this and the DAX (if needed) to use?

thank you in advance