Tricky? Excel365 problem

I have a problem that is causing me some distress...

I have a table (Email Address, Domain, Product, Assigned by <person>?). The first 3 columns are extracts from existing data. The fourth column is a data entry column for specific individuals to select which products they have assigned to give email addresses. To make data entry simpler, I want to use slicers to filter the data to selected domains and/or products for the data entry user.

I have a range using UNIQUE() to extract a list of products to enable the data entry user to see the list of products and assigned totals for the products. The user will see essentially a two-column table with Product and Count of product columns, where the count is products shown as assigned by the user only (assignments made by others are not included). 

For the list, my goal is to have the assigned product count change dynamically (i.e. Setting an "Y" entry for "Bob" assigned? will update the count)  for the user following the slicer values, which eliminates pivot tables without vba behind to autorefresh with each entry (kludgy and time-consuming in and of itself). 

Any thoughts on how to accomplish this would be greatly appreciated...