Thank you very much for this.
It seems that they may have come ashore near where the bodies were found and then pushed the boat back onto the river with much of their gear...the boat then went through the rapids and scattered all of their gear, as well as heavily damaging the boat. That would fit with their pattern of destroying the last conveyance that they used (truck, RAV4, then boat) and everything in it.
In this case they would also have not become separated with the gun. I give more credence to the search worker's offhand comments that the autopsy would tell if it were homicide or suicide now that I realize they could have still held the gun...until I saw that map I honestly thought they were caught in the rapids and lost everything. Now I see them intentionally landing at that spot, ditching the boat and going deep into the woods to die. They ditched their gear because they were in the final stretch of their plan of self-destruction and didn't need anything to survive anymore because they didn't intend to live.
I am also beginning to see KM as more of a decision-maker since it seemed that BS honestly didn't drive (going by the Alberta report). It would have had to be KM's decision to burn the truck and camper that was still worth a significant amount of money and was his to drive and own. KM was also in charge of operating the RAV4 and may have made the decision to torch that as well. Coming from a family with more resources, he might have been the one that got access to a gun.
Maybe KM was the one driving the death march and destroying the truck, RAV4 then boat, the one that held control over the gun, and the one that made the decision that they do longer needed any gear because they were at the end of things. Perhaps BS was so nervous because he was in over his head following KM and couldn't back out because he knew KM was armed. The Alberta man reported that BS seemed despondent at the situation with the bogged down RAV4 while KM worked to get it unstuck and still had the determination to move forward with things. BS on the other hand may have lost all hope and just stuck with KM until KM lead him to the place where they both died at KM's hand?