IMPORTANT: Always make a backup of your save before making irreversible changes.

Open your save file (*.rws) using a proper text editor (Notepad++ or Visual Studio Code). Do not use windows Notepad, it won't be able to handle your save file size.

Search for <Reunion_AllyAvailable>.

Below it you should find a list of pawns, separated by like so:

Delete everything between the opening <li> and the closing </li>, including the <li></li> themselves. It is a looong chunk of text so you need to scroll a bit. You can see where it ends by looking for the next pawn's name in the list.

Save the file and reload the game. Confirm by using Print Ally list.