Not sure if this is what you're looking for, but here's an attempt with the limited scope you've given above.
Assuming your adding a custom ticket field to the Ticket Content section, called Last Editor, and using a combobox for the editor names (or regular text if you wish to add the names manually), that data is kept in two tables, htblticketcustomfield and htblcustomfields.
Here's the test I built to research this question.
1. Added a custom ticket content called Last Editor, Color Combobox (because why not), added my name (Randy).
Custom Ticket Field
2. Added this custom field to my standard helpdesk ticket.
Custom Field added to Ticket
3. Created a test ticket and selected the Last Editor, closed the ticket.
Custom Field in Ticket.
4. Ran the below attached report to find the links. This report is modified from the stock Helpdesk: Tickets closed in the last 7 days. The only added part relates to the two tables. With this information you should be able to use the htblcustomfields name to filter out the Last Editor link with the htblticketcustomfield Data information.
Tables where custom fields are.
Report output.
Select Top 1000000 htblticket.ticketid,
'#' + Cast(htblticket.ticketid As nvarchar) As Ticket,
htblticket.date As CreationDate,
htblticket.updated As LastUpdated,
htbltickettypes.typename As Type,
htblticketstates.statename As State,
htblpriorities.name As Priority,
htblsource.name As Source,
htblusers.name As [User],
htblusers1.name As AssignedAgent,
htblusers2.name As UserLastNote,
htblticket.subject As Subject,
Max(htblhistory.date) As Closure,
htblcustomfields.name,
htblcustomfields.labeltext,
htblticketcustomfield.data
From htblticket
Inner Join htblpriorities On htblpriorities.priority = htblticket.priority
Inner Join htblticketstates On htblticketstates.ticketstateid =
htblticket.ticketstateid
Inner Join htblusers On htblusers.userid = htblticket.fromuserid
Left Join htblagents On htblagents.agentid = htblticket.agentid
Left Join htblusers htblusers1 On htblusers1.userid = htblagents.userid
Inner Join htbltickettypes On htblticket.tickettypeid =
htbltickettypes.tickettypeid
Inner Join htblsource On htblticket.sourceid = htblsource.sourceid
Inner Join htblusers htblusers2 On htblticket.userid_lastnote =
htblusers2.userid
Inner Join htblhistory On htblticket.ticketid = htblhistory.ticketid
Inner Join htblhistorytypes On htblhistorytypes.typeid = htblhistory.typeid
Inner Join htblticketstates htblticketstates1 On
htblticketstates1.ticketstateid = htblhistory.ticketstateid
Inner Join htblticketcustomfield On htblticket.ticketid =
htblticketcustomfield.ticketid
Inner Join htblcustomfields On htblcustomfields.fieldid =
htblticketcustomfield.fieldid
Where htblticketstates.statename = 'Closed' And htblticket.spam <> 'True' And
htblhistorytypes.name In ('Status changed', 'Note added and state changed',
'Internal note added and state changed') And htblticketstates1.statename =
'Closed'
Group By htblticket.ticketid,
'#' + Cast(htblticket.ticketid As nvarchar),
htblticket.date,
htblticket.updated,
htbltickettypes.typename,
htblticketstates.statename,
htblpriorities.name,
htblsource.name,
htblusers.name,
htblusers1.name,
htblusers2.name,
htblticket.subject,
htblticketcustomfield.data,
htblcustomfields.name,
htblcustomfields.labeltext
Having Max(htblhistory.date) > GetDate() - 7
Order By Closure Desc,
htblticket.ticketid
Hope this helps and good luck.