Can't answer about an apache but our 225s have FADEC stops determined by the first limiting parameter, either torque or N1. In twin engine mode in UK at low level its always torque. Max takeoff torque is 100% with a 20 sec transient to 110% - at which point the FADEC stop is reached.
We had an incident where someone had to pull the collective past the 110% point, at which point the Nr of course started to decay. I think he went from 103% to about 96%. The torque remained at 110% - the engine power was reduced by the FADEC to compensate for the increasing torque resultant from the lowering N2.
So no damage was done, no limits exceeded.
On the 225 its only when you get down to 90.5% that the FADEC decides to give you more power - it arms OEI 2 minute rating on both engines giving you an increase in torque that will damage the transmission but hopefully stop you from crashing.
HC