Stone is either an idiot or making a feeble attempt at a PR effort to direct suspicion away from himself.
He says its not him because the indictment says “who was in regular contact with senior members of the Trump campaign” and that can’t be him because he was in regular contact with Trump directly. The indictment is being purposely vague here as to not reveal information that they are not ready to reveal. Trump is most certainly in eluded in the subset of “senior members of the Trump campaign”, and if anything he is establishing a direct flow of communication to the Russians through himself, likely to Trump’s peril.
