With nothing connected to the controller wires, this sounds OK. The 5.5V is a little high, but it could just mean your battery in the multimeter needs replacing. If the throttle is connected, this is not right. Red to Green should be a little lower in voltage.

Try this. WIth everything connected, what is green to blue? SHould be less than 1 volt and when you roll the throttle, it goes up to 4 volts.,

If this is what you see and the motor still doesn't work, make sure the ebrakes are not engaged. Like you might not have the cables connected or the cables connected, then the levers will hang loose and they have switches that inhibit the motor.