Razie, I remember your arm movements from videos from earlier this season and last season along with some of the following MA. It seems as though that, in the process of making subsequent adjustments, you have eliminated the same amount of movement in both arms thus effectively eliminating ALL the movement in your right arm. However, now your left arm movement looks fine. From the way it looks in this video along with some of your comments regarding possible arm fatigue and that "it just won't move", I might recommend having it looked at by a PT, etc., if you haven't already. Sometimes we have injuries that we ignore and brush off as typical aches and pains, yet allowed to persist and have effects on our technique. You are a good skier, but where you are right now may not advance very far until you get your pole plant issues taken care of.
A recommendation I would have, as I would for any skier looking to improve, is work on it over the off season on inline skates. If you are already or can get to a level of carving turns down something relatively steep, it is very difficult to do it without a very consistent, properly timed and facilitated pole plant (unless you brake from ski technique all together). At your level of skiing, I would surmise that you all ready are or could be carving turns down slopes as pictured below, about 30 degrees (?) by the end of the summer. On a very short and non-skidding base of support, the "herky jerky" movements and any absence of fundamentals that skiers may get away with on snow are simply not tolerated. It is easy to work up to that because it is easy to find progressively steeper pitches to skate. Industrial park access roads on weekends is a good place to start looking.