Well if you haven't got it sorted yet, you can try this-
If it really is a stubborn smell, wash the hide in some petrol (mind you, it might be a bit expensive these days) and then hang it to dry for a few days, and the petrol smell, and the animal smell will go.
If you don't like that idea, you can make up a mix of-
1 gal. hot water, 4 cups soap powder, 2 lb washing soda, 1/2 oz borax powder, cool to luke warm, then add 1/3 fl. oz. of sassafras oil.
Wash and soak skin in this for 1/2 an hour, then rinse in warm water, and re- break the skin.
You can buy sassafras oil from some chemists (drugstores).
Borax is just a cleaning agent you can get from the supermarket.
You can also wash the skin in petrol, then the other formula if you want.
The petrol method can damage some leathers though.