Do the indicator lights on the dispenser pad change with button presses (crush, cube, water, etc.)? If so, that pretty much rules out the dispenser board.
On this unit, the main PCB supplies 12vdc to the water inlet solenoid. The fact that it's making ice means that 1) the main PCB is working at least for the ice maker side of things and 2) that the isolation valve and the ice maker side of the water inlet valve are both working. You can check continuity of the dispenser water coil. If that's good, then all you're left with is the dispenser lever switch and the main PCB.
Use a jumper wire and jumper out the contacts on the dispenser lever switch. Depending on the function selected on the dispenser display board, you'll get water or ice if that switch is the problem. If not, then the main PCB is bad.
Here's the service manual for this model: http://appliantology...service-manual/