There would appear to be two plausible theories at this point.
1. They are holed up someplace with enough supplies that they don’t need to surface in public and are disciplined and knowledgeable enough not to communicate electronically in a way that can be traced.
2. They are dead in the woods from hypothermia or murder/suicide.
Every day that passes makes theory 2 the more probable.
I do have a fancy version of theory 1, but it requires undetected travel to the Manitoba/Ontario border and knowledge that two guys from Port Alberni are unlikely to have. If they headed out Lake of the Woods with a canoe and basic gear, good luck finding them among the 14,500 islands, and figure on expanding the search to the United States.
What about their abandoned car as evidence, if they got to Lake of the Woods in a vehicle? There are very steep shoreside drops, easy to make a car disappear.