I read that there were weapons found abandoned in the burned out vehicle along with cold weather camping gear. He was obviously going to go up there in the mountains and lay low for a while but it all went south for him when the axle broke. A broken axle in rough terrain is a plan spoiler big time. He must have continued on foot as he took only what he could carry, leaving the rest. I'm sure they have searched all possible shelters that are known in the area. No further actions/murders have been associated with him since. That leaves about three possibilities.
He got out of the mountains and is recouping in a safe place.
He is still up in the mountains and has found a way to survive.
He is still up in the mountains and is dead, by suicide or the elements.
They are continuing to search up there. That tells a lot, and also means that they have no definitive leads causing them to shift their focus elsewhere.
If he is dead, finding the body may be very difficult. Wilderness areas conceal bodies extremely well. Usually the deceased hunkers down low or under something before expiring. Leaves, etc., blow over the body. The animals come. And then of course with the snow covering everything you may walk right by and never know.
I also read that the tracks or footprints they had been following were discovered to have probably been made by someone else. Don't know if this is true, but it means nothing anyway. A human walking lightly in most terrain does not necessarily leave "tracks". Dogs could pick up the scent but frequently lose it at some point.
I've seen the quiet dead; and I've heard the living moan. This world's no place to live in, but it's home.