Have you tried to see if the second joystick is picked up by jstest? I seem to recall that if I ran emulationstation and setup the controllers. It never told me again how many gamepads were detected. unless I connected a completely different device. I could be remembering incorrectly though.

When you added the quirk to the end of cmdline.txt. It was at the end of the single line. Correct? You can’t create a new line.