Interesting video. However, nuclear reactors can’t generate a nuclear explosion.
Except Chernobyl and even that one is subject to debate. For years after that, even physicists and engineers went with the assumption that steam pressure blew out the containment building. One of the first things Yeltsin did after the USSR collapsed and Ukraine became independent was to declassify evidence that the Chernobyl reactor briefly went supercritical before flash-boiling even had time to be a contributing factor to the ensuing blast.