Hi can you test in your game. I have replaced part of the motion data for the move with the data from 2k18 which is slightly different.
The move is the same. This is just the timing data and a few other bits which enable the move function in gameplay.
Place the 51_param.pac file in the pac\ingame\motion\body folder.
Ok. I did preview the move and what you described usually occurs when the finisher is triggered with the character facing the opponent.
I think this is due to some of the motion data in the 2k19 move. I notice it didn't occur with the 2k18 motion.
What I will do is replace the data with the 2k18 motion since its the same move and send it if you can run a few tests later today.