Pete - He soaks the head, but that is all I know of the process. I don't know if he also simmers after it soaks.
The ones I've done like that really did need to be aired for a few weeks even after being treated with peroxide..
I've found that even the antlers themselves smelled after being immersed in the funky "soup" for a few weeks..As you don't want peroxide on those, I cleaned them several times during the airing period with Detox, just to kill the bacteria off...