I would not recommend connecting the two +5V supplies from both controllers together, so try connecting the ground and signal wires to both controllers but only connect the +5V wire to one controller
(like you should have already done with the +5V wire on the throttle ).If the throttle +5V wire is connected to the front controller, then connect the PAS +5V wire to the +5V supply from the rear controller to help spread the load.
However, if you already have both +5V supply wires connected together and have not experienced any problems with either +5V supply, then it might be OK to continue sharing them for the PAS sensor.
If the single PAS sensor does not control both motors correctly, you may need to add another sensor
(using the same magnet ring) and then wire the two sensors separately to each controller.
Alan