Do you know who claimed they had explosive belts? I don’t because the Wikipedia article doesn’t source it.
And if you read the citation for the claim just after that, you will see that supposedly many terrorists- the ones supposedly wearing explosive belts- escaped rather than blew themselves up.
That sort of cognitive dissonance couldn’t possibly be put out by the otherwise totally honest Russian media which is definitely not a political mouthpiece for their dictator, a man who gassed a theater full of innocent hostages but definitely did not blow up a school full of innocent hostages.