First make sure your dedicated server is stopped, now find the directory,
( SteamCMD/steamapps/common/Outpost Zero Dedicated Server/WindowsServer/SurvivalGame/Config )
Look for (DefaultGame.ini)
Now edit this file and look for the line
[/script/survivalgame.survivalsavemanager]
DefaultSaveSlotName="Default"
bAllowSaveOperations=True
bAsyncSaves=True
AutoSaveFrequency=900.0f
bSeparateSavesByUser=False

Change (DefaultSaveSlotName="Default")
to (DefaultSaveSlotName="Whateveryouwantsavegame")
Save and exit, Restart your dedicated server, This will create a new game.