When browsing the game files, I found a folder that contains the thumbnails of all game modes that are currently featured in quick play (Random Map, Empire Wars, Battle Royale) as well as thumbnails for all other common modes such as Deathmatch, Regicide and Sudden Death (see below). These thumbnails were created on 18th November 2020, so apparently it was planned to have all modes available for the anniversary update.
Would you like to have more variety in quick play?
