Go to Admin panel -> Settings -> Tickets.
Click on Queues.
Click on Closed.
Click on the Columns tab.
(If its not already) select --Add New-- in the drop down on the bottom left.
Under Primary Data Source, select Help Topic.
In Name type in Help Topic.
Click Save. (The pop up windows will disappear when you do)
The drop down where you selected --Add New-- should now say Help Topic. Click Add to the right of it.
Make room for your new column by resizing the other columns.
Drag the new column to where you want it in the list by clicking and holding the button on the little up/down arrows on the left and drag.
Click the Save Changes button.