This story fits the pattern of numerous warnings about Mateen to authorities. It fits the pattern of a 10 month investigation of warnings and a complete lack of action by the Obama administration.
Do you disbelieve every story about warnings to authorities or just this one? Do you disbelieve because you feel no Muslim would report Mateen?
I am not one to trust the media. The media may be lying. The story may be untrue. But why do you not believe this specific story?
As black dog states useful cover to show that Muslims are reporting potential Jihadists. Protects the status quo.