This is incorrect...The ground fault protection at the inverter will only operate correctly if it can see a connection between its ground and the metal components on the array.
Ground fault has NOTHING TO DO WITH THE GROUND WIRE...
ground fault devices will trip when there is an imbalance of energy between the conductors.
If more energy is transmitting on the hot wire than is returning on the neutral or other hot wire, the gfci will interrupt the current.
It does not require a ground wire to do this...