To be fair, Ben isn't drawing the same conclusions as the "mind control" advocates. He seems to be strongly suggesting that more than one person was involved, thus enabling the purchase of a large cache of weapons and bomb making materials, the required expertise and (possibly) team-work to create bombs, and tactical support for the massacre. No where in Ben's reporting does he mention the CIA or MK ULTRA.
The suggestion that more than one person was involved: Worth asking about and finding out.
The suggestion that this was a result of CIA mind control: very unlikely and not well supported by the evidence.