Slicer Challenge

Hi - I'm looking for some help in solving a slicer problem.  Here is the scenario - suppose a bicycle manufactuer company (BikesUSA) has three departments.  Each department makes both critical and non-critical bike parts.  (critical here pertains to a specific manufacturing criteria; not bicycle function).  Department A makes hubs (critical), spokes (critical), and rims (non-critical), Department B makes frames (critical) and handlebars (non-critical), and Department C makes tires (non-critical), grips (critical), and seats (critical).

The first goal is to make a table that will display only critical part types in the rows and a count of pieces manufactured by quarter in the columns.  A slicer will allow the user to select Department A, B, or C, and each department's critical parts will be displayed.  I did this first goal simply by creating data element that indicates whether each part is 'critical' or 'not critical' for each department and placed that field as a filter on the table (filtered to 'critical'), then added a slicer for department.  Works great - so far so good...

Here is the actual challenge: I would like to show on the table a view for for critical parts for all of BikesUSA.  However, the issue is that critical parts at the BikesUSA view/level is not the same as the all of the critical parts for all of the BikesUSA departments combined.  At the BikesUSA level, management considers only hubs and handlebars as critical, so selecting all of the slicer selections won't work.  The goal is to have a slicer selection available for the BikesUSA management that only shows hubs and handlebars.

Thanks very much for any thoughts you may have!