would be more with this thought pattern also. Although oil getting past un seated rings is not impossible you would have noticed the crop duster look behind you in the mirrors as it would burn the oil.
Though my biggest concern with this theory with the oil filter is I doubt the level will drop that extrememly. Filters have a limited capacity and unless it has a “flap valve” or check valve to bar oil escaping back into the resevoir it should still be in the case. I would echo what the others have said and 1) get the dealer to check it out and 2) unless completely satisfied with their answers make them replace the entire bike. Even if it was human error the damage has potentially already occurred.