Oh, man, I feel ya!
That smell is really very hard to get rid of. Wiping down with a little bleach will help. but the smell gets absorbed into the plastic liner, and will soon be back. If there's any way you can turn the fridge off, and leave the door open wide, with all the windows open and let the whole thing air out for, oh, the next year or two . . . .
Just plain charcoal wouldn't do much. I would think you'd need activated charcoal, and lots of it. Go down to the aquarium/pet store and buy several boxes of the activated charcoal they sell for aquarium filters. Spread it out on paper towels, after wiping the fridge with diluted bleach.
Good luck.