Ehh technically you can, but just verify your installation first. Do what the installation guide tells you to do, but point the download to your bo2 folder instead, and deselect "create subfolder". That should verify and skip over whatever you have and download anything you don't have. Also only reason I'm mentioning this way are because their repacks are usually clean, last I saw or else I would ask you to do a clean install if it was any other repack (nosteam/skidrow).