Apologies in advance for how gruesome this thought is:
Would BM kill an elk out of season, process the carcass keeping the meat in a cooler(s) and then leave out the skull/tissue out and possible some additional meat to lure mountain lions? Would BM then murder SM, cut up the body and hide the human remains under the processed elk, and then go an dispose of the elk, human remains, and coolers? And then need to clean off your saw thoroughly with bleach? Perhaps even all of your tools if the saw was placed back in a tool box to avoid suspicion.
Also, would disposing of elk steaks with human remains increase the likelihood that an animal would come and eat/take away both aiding in the disposal of the body and difficulty in locating it?
And if this actually happened, is there some Freudian aspect of BM saying that a mountain lion got her? As that was his intent all along, just not in a bike ride scenario?