Work around to Filter Contacts by Email Subject Title (Bulk Send) ?

I want to be able to see WHO opened emails from a specific Bulk Send / Group Email, and then be able to send those contacts a followup message.

...Has anyone figured out a workaround for this?? (with zapier, zapier + PD workflow, or otherwise).

It looks like you can't:

  1. Export notifications from Sales Assistant (where it compiles who opens emails with the name / email),
  2. create an email filter based upon Email Subject Title,
  3. create a Person filter using an Email Subject Title.

Any help would be appreciated.

This seems like it should be a given...? Maybe I'm just missing how to do this...?