Question...how is it "fake news" if the person who had the gun pointed at them admits it really happened?
Was the firearm pointed to be threatening or just sloppy muzzle discipline? While the latter can be every bit as lethal as the former, conveyed hostile intent might be more what determines whether a person felt threatened (and whether they had enough sense to know they could suffer serious injury or death).
If the incident did not involve hostile intent, the headline can be written in such a way as to lead the reader to believe the incident did involve hostile intent. That would be misleading and hence "fake news".
I think there should be a separate category for misleading headlines, or those which neither reflect the content of a story or remain unsubstantiated by it, simply because of those out there who read headlines, but for whatever reason don't read the story (maybe reading the back of someone else's paper).