Properly defending the Darth Vader grip is important to minimize the risk of submission. Instead of grabbing the wrist, try using the lapels.
More in this mini-series:
Darth Vader Foot Sweep https://youtu.be/GA4N8rcliBU
Darth Vader Loop Choke https://youtu.be/AqrjmEkqT24
Darth Vader Baratoplata https://youtu.be/N8SQnwl0Wa4