The torque you see is not a FADEC output, it is an actual torque measured on the high speed shaft. When the FADEC limits on Ng or TGT you have reached a power limit so the fuel flow is effectively frozen and if you demand more power, torque will rise and Nr will droop. When you reach the torque limit (which from memory is a genuine Tq limit but I could be wrong) the fuel flow is varied to maintain constant torque. As you demand more power Nr droops, fuel flow decreases and torque remains constant. If I am wrong and the ultimate 'torque limit' is actually a power limit then torque will rise as Nr droops just as it does when you reach an Ng or TGT limit.