Views filter to find rows where column B = bar, limited by column A = Foo

In D8 I have a custom compound field with subfields that reference taxonomy. 

So, essentially, I have one table in the database, containing a column for each subfield.

What I want is to be able to search on a couple fields together, with an exposed filter.

The user has a dropdown of available values, bar-1, bar-2, bar-3 in Column C, where Column B = foo-1, this would narrow their results for related entities (column A).

There would be several of these dropdown, each one limited by a specific value in Column A (Foo-2, Foo-3, etc.)

A simple filter can give me all the options in Column B, but with no way to limit by having Foo-1 in the same row. I looked at the Group filter, but it doesn’t seem to be the right tool ( or I’m just not understanding how it works?)

I’m hoping there’s a trick (and/or tutorial) for this that I’m not seeing …before I give up and force myself to learn how to build custom views filters in D8.

Drupal version: