Well, the Lockheed Constellation didn't get its reputation as the best three engined airliner for nothing!
They frequently turned up at their destinations with one engine out after having crossed the Atlantic
A three engine ferry applies to taking-off and flying the route with 3 engines and pax.
An engine failure en-route is the decision of the Captain. In this case a simple engine malfunction with three remaining.
What is the point of ETOPS? To allow two engined a/c to fly extended range on one engine. This a/c had three!
I'm sorry to hear that he was somebody you knew. Notwithstanding some of the other comments here I do feel that the regulations in NA are lax compared to the UK. Yes, there's a lot more GA than in the UK, but! In the UK no one is permitted anywhere near a major airport without having followed the correct procedures. i.e. filing a flightplan, having the minimum required radio equipment, etc. In the case of a VFR flight PPR (prior permission required).
Here in Italy where I am based (I do training courses for ENAC). no one is permitted at all under any circumstances in controlled airspace without the minimum qualification in English of ICAO level 4.