I'm not sure where you are getting that "law enforcement themselves are not sure anymore", as that is not at all what law enforcement actually investigating the crime is saying here. Mateen had a plethora of evidence on his computer, cell phone, contacts, etc. that he had become radicalised for some time, with numerous statements made by him to those around him, as to his radical Islamic beliefs. Indeed, one the the people who reported him to the FBI before the attacks even happened, was from the Mosque he attended, who was worried about his radical beliefs. I'm baffled that you are unaware of this.