Reports are that the passenger in question walked out the door and down the stairs to his medical escort.
(the captain)... had to act on the information given to him ....... by any qualified medical professional on board.
Exactly. 25 years after we started training CC in use of defibrillators, and the Phoenix medical support service became operational, it is staggering we allow 'doctors' of unknown provenance, who have no aviation knowledge, no knowledge of the effect of decompression, and no information on the medical facilities at the destination or diversion to make decisions. While I accept that a doctor my have an input if a patient has a cardiac arrest, we should be circumspect about any volunteer's qualifications and look to bolster the training of CC especially on long haul. Some years ago a meeting suggested a subset of CC could receive additional medical training which would not only be cost effective but good for customer satisfaction in this case