Barannfin,
Interesting question.
Here are a couple of previous postings by H-43, on the intermeshing Huskie. Perhaps the situation is similar.
H-43 on PPRuNe ~ July 26, 2001
As for turning when the pilot makes a pedal input, the pitch is increased on one set of rotor blades and decreased on the other by a mechanical mixing system. The resulting higher torque from one rotor system rotates the helicopter. Also, at the same time through the same mixer one rotor disk is tilted forward and the other back helping to turn the aircraft. The only bad part of this system is that at some power settings it is ineffective. This in turn can cause some interesting moments for an inexperienced pilot. I remember the first time it happened to me. As I was approaching to land the nose started wandering off to the left so I added right pedal and added and added right pedal until I hit the pedal stop and we were still turning left! About this time, the other pilot flying with me told me just to add a little collective and the problem would correct itself. Sure enough it did but it was still one of the more interesting moments of my training!
H-43 on PPRuNe ~ September 7, 2001
As far a pedal unresponsiveness is concerned, I really don't know how the K-Max is set up or how it flies. But the Huskie is unresponsive because it uses differential pitch to cause yaw. In an autorotation the requirements change so there is a mechanical reverser assembly that changes the direction of the differential pitch change pushrod. At a certain low point in its travel the reverser output rod will not move at all no matter what the deflection of the pedal input. This complicates thing during low power settings such as during a descent.
Edited to add;
Apparently, there is a, yet unannounced, method of handling yaw for the next generation of intermeshing helicopters, which is said to overcome yaw control problems.
Dave J.