It's not clear whether the FBI ever made contact with the individual who left the YouTube comment. The FBI and the bureau's Mississippi field office did not immediately respond to CNN's requests for comment.
Then, on Wednesday afternoon, after Cruz was arrested, Bennight got a call from an agent in the FBI's Miami field office, who wanted to follow up on the September incident, he said. A few hours later, FBI agents from the Mississippi office paid Bennight another visit.
"I saw the story kind of go across my newsfeed but I didn't pay a whole lot of attention to it, but when the FBI said it was the same name the first thing that went through my mind was, 'Wow, I hope you were at least watching this guy that I alerted you to months ago,'" he recalled Thursday in a phone interview with CNN.