I had a sore forearm the last six weeks of ski season too. Three weeks into season end most of the pain is gone. At its worst I couldn’t hold the rope when on -side wake crossing (sore right arm, RFF). In fact my right arm was needles and pins when walking and my pinky finger was numb constantly! Probably had some rough pull outs and high side falls but nothing memorable.
Time has healed things 99% but to avoid re-occurance I’m also wondering if my hands are still too high and my handle “death grip” are contributors to the pain.
When exactly are your elbows pinned to the vest...at the beginning of the stack, at the white water or directly behind the boat?
Photo is free skiing 51 Air. About the same water temp!