What was found
PILOT STARTED NR 1 ENGINE, AND RAN UP TO GROUND IDLE. PILOT STARTED NR 2 ENGINE, AND RAN UP TO GROUND IDLE. PILOT FELT THUD AND HIGH FREQ VIBRATION IN THE AIRCRAFT. PILOT THEN SHUT BOTH ENGINES DOWN. THEN INSPECTED ENGINE COMPARTMENTS, AND FOUND NR 2 ENGINE TO TRANSMISSION DRIVE SHAFT TO BE BENT AND TWISTED. MAINTENANCE CONTACTED TECH SUPPORT. TECH SUPPORT FELT THAT THE CLUTCH DID NOT ENGAGE UNTIL NR 2 ENGINE WAS AT GROUND IDLE. TWISTING THE DRIVE SHAFT, WHEN IT DID ENGAGE.