This is not something I usually see. In fact, it is usually the opposite.
Over-active right bicep muscle, not Releasing the Fourth Power Accumulator sufficiently, Off-Plane, fear of hurting the right elbow are places to begin...Is the player even capable of physicaly straightening it ?
Per 7-1, For the Swinger, CF Uncocks both the Left Wrist and Right Elbow; 7-19 and 7-20. So both must remain Passive, but never Whippy.
Per the Magic of the Right Forearm and Tomasello's instruction per Homer Kelley.....For the Swinger, CF Uncocks both the Left Wrist and Right Elbow....yes, the golfer uses the right forearm to start the uncocking of the right elbow from the top (see 7-3 and 2-N-1 from the 7th edition)....CF Uncocks both the Left Wrist and Right Elbow.....at Release. There are the two words missing from 7-1....AT RELEASE.