Yes, that is pure speculation. It's nothing approaching evidence. Even the guy in the video admits that that's a non-thing; it's only the plagiarism idea that made him doubt it, and as noted, that's a bust.
You want to answer the question "Why didn't you mention this in your earlier report?" with the answer "Because it's made up"- that is the point where you are just speculating. By any rational measure you need far more than that to make this a serious accusation.