[Sans Peur]

If the generator clicks then it is getting power. Have you metered the power to the starter solenoid? That will tell you volumes. First confirm there is full power to it. Then put your meter on the switched side of the solenoid and try to start the generator. If no power to that side, it is the solenoid. If power flows through move to the starter and check it.
Also, have you tried to start it with the switches mounted on the generator itself? I had a problem with the remote switches once. They wouldn't do anything but click but it would start fine on the internal.panel.