might be helpful if post the slow motion one where it is missing the trunk. I'd shoot it from directly above and then from the side. If the issue only pops up with the glass on, seems likely it is nicking the glass (which the side view might show better than the top view).
Missions were always intended as a set of objectives for higher skilled players and to give breadth to the game. So success with Missions requires developing the skill to make the four right side shots when the ball is coming down from the left orbit.
The first two are practically gimmies, especially since the magic stand-up support for missions was added. The third one is certainly attainable if you are trying to make it and I don't think that requires a 'super game', as you can easily get it by accident.
The fourth is certainly much, much tougher and does require a certain degree of skill and precision and is not just going to happen without you focusing on it, very unlikely it just happens. It is also a very different set of shots than the others so skill developed for the first three is of no help on this one.
The fifth one is equally hard, but only because of the challenge of the second shot (milkcan off of a made left orbit shot), but what really makes it challenging is the pressure of it. After you make the difficult second shot, your mind jumps to "ok, now don't blow it" and considering the last three shots are shots you made on earlier missions, at that point it should not be super hard, but, well, the mind can . . . . What is also challenging ab out it, is that over time you try to train yourself to always go ramp after milkcan, but for the mission it is right orbit, not ramp, and while that is an easier shot than the ramp it may not be, if your mind is thinking 'ramp'.