I have no basis to conclude anything in this matter. I saw multiple news reports/interviews to that effect. True/not - you get to decide based on news you hear.

Do you have a basis to conclude that "every intelligence and law enforcement agency that has looked into it and published a report has found the opposite"? You exhaustively went through all Western intelligence and law enforcement agencies and read their reports? So you are quoting other news articles/interviews. Apparently their views differed. Ok.