Multiple Motion Controllers

I successfully tried out the motion controller interaction and inputs via blueprints.
In the VR documentation is specified that only 2 motion controllers can be set per HMD device (left and right controllers).
However i connected a third Vive Controller and Steam VR was enable to pair the third controller being connect yet the others two controllers.
So i guess the SteamVR plugin can track multiple motion controllers.
My question is, in UE4 how can i get position/orientation or anything from a third controller, having only one HMD headset?
Thanks in advance!