YES. The VC-6 cable connector (15 pin male "D" type connector) fits into the VC-8 controller (15 pin "D" type female connector) and the wiring is setup, so that the VC-8 controller allows proper control of Valves 1-6 of the VC-6 pinch valve system (according to Guy).
In general. The VC-8 can control up to 8 pinch valves, or up to 8 PTFE valves, or up to 8 mini valves with the VC-8 controller. The VC-8 actually recognizes each valve type. So, no adjustments need to be done when switching the valve type. That is one advantage of the VC-8 over the VC-6.