I feel sorry for the good samaritan. Next thing you know lawyers will be suing because there is not a crash cart at every gate and then every gate will be equipped with one. Then they will sue because the people are not always professionally trained and then... I can sleep more in the morning but this nightmare never ends.
I have a feeling that he'll do fine. He did the ethical thing, and I assume exercised the care and follow-through that a similarly educated and trained person would find prudent.
Not sure how the airport will fare, there are good arguments on both sides. Does the public have a right to expect defibrilation facilities? Does the airport have a legal duty to provide them? What are the ramifications of providing a feel-good impression without the ability to deliver the help? Similar to the impression that police presence gives, that they have a duty to help a person in distress, yet crime victims have no recourse aganst a police department for failing to prevent crime.