To start, here's my data structure. Each month I receive ~20 files that look like the below. 4 tabs, identical schema, 4~25 records.

I need to extract the business unit (QQQ) from each sheet (it's the same for each workbook). In theory I could take this from any string that contains it, including the file name, but it's only in a consistent format in cell A1.
I then need to combine all worksheets/workbooks.
Attached is my workflow that can do either part (combine, or split BU) separately but I can't figure out how to join them together.

This is what I want the combined output to look like (and what Container 2 outputs for a single sheet):

Container 1 combines all workbooks in a specified directory.