Yes same! I've got the bad ending as well as the neutral ending but just can't seem to unlock the good one because he always thinks I've touched the orb even if I haven't.
I just got the best ending. He accused me of touching the orb anyway but there is one really subtle difference in my playthroughs for the 2nd and 3rd endings. When you're about to get on the boat with your friend, do not touch the orb on the beach.
I never found a glitchy boss behind any paintings though?