Two cups of water splashed around are not going to cool down thick sheet metal that has just been blow-torched. And nobody in their right mind would be sticking their bare arm through any hole immediately after the last quarter inch has been blow-torched either.
Seeming error. I realize that 1957 was an earlier time with different methods and equipment, but the medical professionals--including two doctors on the scene--were way too slow in waiting until they got the boy into the ambulance before beginning to attempt resuscitation. Today, resuscitation attempts would begin as soon as the medics got their hands on the patient.