Alex.J
[14] Master
You are implying that Kami is actually fighting. In the DC universe it doesn't seem to be a secret anyways that he is weak to rocks. Goku has survived moves that blow up planets. Pretty sure he can take a punch from someone who relies on handicaps.
Well i'm assuming the scenario would be they meet each other for the first time and fight. Not Goku doing months of research on how to beat him. Within that month, he'd probably be dead anyways.