@The Staff. Theres no link point to the archive. You have the Forum is Active status set to no. It won't appear if set to no, but remains accessible if the forum's URL is known, and if you search all open forums.
Every now and then I get some search results from this catogory.
https://vborg.vbsupport.ru/forumdisplay.php?f=31
Though this link is not viewable anywhere on vBulletin.org. Maybe you should make it viewable like vB.com has there archive forums set. At the very bottom in its own forum.