I'm wondering how this was actually strung up over the beam - if his side had a shorter lead point, he would only have so far to go when the chair was dropped - assuming the lead was wrapped over several times which would indicate to me, this wasn't the first time something was hung from there? JMOThis is a strange question, but ...
The boy looks much heavier than the girl, so if they were found hanging on opposite ends of a chain that was over a support beam, when the chairs were removed, wouldn't the boy be standing on the ground while the girl was pulled to the ceiling? I'm having difficulty understanding this picture.