You can't. How are you going to repair the gas pipe inside the wall unless you cut a large opening in the outer wall to get access to the pipe. Then pipe would need to be repaired & system recharged with correct gas. Time to buy another fridge I'm afraid. Next time don't drill holes through fridge walls.
Doug
March 2010
I can answer this question...
How can we repair a hole that was drilled in for locks ?