Maybe I am missing something but is there a way to display the user's full name (that was keyed in under contact info when they created the ticket initially) on the Ticket info screen. Say under the User (which comes from the email file). Our email address are just department email addresses and they don't reflect the actual name that was keyed in on the contact info when creating the ticket.
emails are linked to a users name.
Don't know if that helps in your case, but did you try to change the default name formatting?
Admin panel > settings > system > default name formatting