I don’t know what to say. You say the clutch works fine but it won’t disengage. To me that’s NOT fine.
Check where the clutch pedal connects to the clutch cross shaft to see if the roll pin has been sheared. That’s the easy part. If the roll pin isn’t sheared and the shaft rotates with the clutch pedal, then the pins in the yoke have sheared, and you have to split the tractor to repair it (I believe).