It went undiagnosed/misdiagnosed. He had inconsistent pain throughout year. It’s not impossible in certain situations to pitch w partial UCL tear. His arm never strengthened. As a projected high round pick he had mandatory pre-draft MRI and was medically red-flagged.So was he pitching with elbow damage all year? That would certainly explain the fall off in performance.
He seems like a classy act. Good luck to the young man.