Should be. You'd jump the power-on pin with a ground pin with a bare metal paperclip. I couldn't say if it uses the same pinout as the desktop Beige G3 or not.
Based on the teardown I found of the G3 AIO. It looks like PIN 14 is a blue wire and the others on the row of 11-20 follow the pattern of the G3 tower PSU. I'd assume it is the same pinout. You could use a multimeter to check.