No, the eventual outcome does not validate the hikers response. They might have survived DESPITE doing nothing, not BECAUSE of it. Nobody will ever know the answer to that one.

Me, I would interpret trying to tie me up to a tree while holding a rifle on me to be a true life threatening situation, deserving of the most violent of defenses if needed. This includes terminating the aggressors life if required. Others can certainly disagree with me, that's fine, and the discussion is welcomed. Some believe that passivity is the solution to force, others believe force should be met with equal or greater force. People have lived, and died, utilizing both responses. Conclusions drawn from anecdotes and single case examples of what may have worked in one specific situation are meaningless and dangerous.