I cleaned an old elk head that may have been boiled, we didn't know the history. It was very yellow and had dried meat in the nostrils. After macerating for 2 weeks, I hit with a garden hose and hot water. Lot of filmy stuff came off the bone. Degreased in dawn a few days. Let it dry well and painted on the peroxide. It took about 3 treatments but came about 90% of normal white. Had a couple of spots I just couldn't get to turn white on it. Looked and smelled way better though.
Its always low risk due to the low temps. I'd give it a run in the degreaser for sure. If water gets cloudy just rinse and repeat.
