Filtering pivot table on dynamic list

Hello

I'm trying to filter a pivot table on a dynamic list of names. So, basically I have a script that generates a list of client names based on a set criteria. This list changes on a monthly basis. It can have upto 90 names, with possible dupes. On a separate tab i have a pivot table on client name, account and product. On clicking a command button I want to be able to filter this picot table by only the client names on the previously mentioned tab. Any clients not in this list shoud be filtered out of the picot table.

Is there any way to do this? I attach a sample file. The list is on tab "Drilldown", col Z. And the pivot is on Sheet 4

Thanks!