The original story was indeed a cheap knockoff. In an interview afterwards he said that he had since bought a real Leatherman tool because the saw was so bad on his cheapie.
How he plans to saw his other arm off I'll never know!
Still, Leatherman couldn't come up with better marketing than this, so I imagine when the opportunity arose to have this movie made, they probably threw lots of money at it to make sure the knockoff was replaced by a real one.
Def