Excel Userform combobox or checkbox?

Hello - - I'm looking to use a userform from Excel that will act like the filtering of a spreadsheet. The reason I want to use a userform is that this will be made available to another department so I want some flexibility with providing a breakout of what's being selected via the userform.

So, what I have is a list of employees, about 13k rows and 10 or so columns. The columns are like Name, ID, Main Dept, Dept, Sub-Dept, Cost Center, Cost Center Description (L), Job Title (F). I'd vision this userform to have a combobox (multi-select) for 1) Main Dept (I), Sub-Dept (J), Cost Center Description (M).

A textbox will show the entire count, say 13100. As the user selects from the first combobox, Main Dept, (for example Technology), the textbox reflects at total count of say, 5000 employees. When the user selects the next combobox, Sub-Dept, that all departments that roll into Technology are listed and if the user check or selects two departments in the list, the texbox shows the total from that, say 2000 employees. From there a user can select Sub-Dept and/or Cost Center...and so on.

Hope that makes sense...I'm attaching a mocked - test file for review..

Update - after some review/research, I think what I need is a series of listbox (multiselect set to 1), where by after each item selected the row count text box updates...Hoping someone might have example of two multi select boxes and the text box...Thanks for reading!