I don't keep much hope on somebody looking in the discussion section for this problem with all that time passed after it's introduction but I would like to make the note that the view point  should be with non-negative x coordinate. This is not clear from the problem statement. I still haven't passed the whole problem but adding this logic to my solution upgraded me from wa8 to wa9. Any other tricks someone has noticed?

No, view point may have negative x coordinate, so there should be another reason for your advance from 8-th to 9-th test...