Find e-mail address in incident thread

Summary:

How can I make a report with an e-mail address in one column that is used to search in the initial customer thread in another column. With a third column showing whether that e-mail address was found in that thread.

Content (required):

I want to verify whether forwarded e-mails to my OSC instance containing the original e-mail address in the initial customer thread, can be matched to the e-mail address that the agent sent the reply to.

Therefore I was working with the transactions table to filter on response sent transactions type and then to show the e-mail address in the transactions.description field. Now I’m struggling how to search with this value in the original incident thread. I noticed I can use incidents.search_thread as a field to search on, but then I need to search each row containing that specific e-mail address in its belonging thread which I don’t know how to do. Your help is much appreciated.