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If you've already tried shorting the pins (the ones a bit diagonally either side of the "G", right?) and still didn't get anything, that would tend to suggest another component.
If it was a broken switch, that should have caused the keypress to register.
If in doubt, really press down to cut through any flux that is covering the solder joints - I would tend to use two pointed probes and poke them at the solder blobs for the G switch.
If it was a broken trace, it would probably affect other keys in that area, which you said it doesn't.
Perhaps one of the other components around the G?