Complex sentence: Later in Carl's room, Bart Oates appears, much to Carl's excitement who recounts his stats and the many games he watched, ending with his memory of hoping Oates gets injured upon finding he'd transfer to the 49ers.
Split into simpler sentences: Later in Carl's room, Bart Oates appears, much to Carl's excitement. Bart recounts his stats and the many games he watched, then Carl reveals how he had hoped Oates would become injured after he transferred to the 49ers.