How to add "Last followup by" in front/ticket.php and not only "Last edit by" ?

Hello,

I would like to know if there is a way to have a column in front/ticket.php to have not only the "Last edit by" but also "Last followup by" in order to setup more specific search terms.

My goal is to set a "Saved search alert" on this criteria so that when a customer has replied to a helpdesk agent, I know that this ticket doesn't have any answer.

Currently, I go this way :

Why the "Last edit by" is not sufficient for me, because any supervisor could come and edit the ticket, to insert for instance comments, tasks, etc. and will be, the "Last edit by".

Has anyone found a way to do it ?