There has been far too much focus on the engines and very little on the way the pilot handled the emergency. What no-one has really alluded to (perhaps in deference to the late pilot and his family) is the unwillingness of the pilot to land the aircraft while he had the opportunity. The first engine failed well before he was over water, and there were a couple of airstrips along the path that would have been suitable for an emergency landing (Kadina for one). The terrain on a reciprocal path is flat farmland that would be the least worst alternative if an off-airfield landing at night were required. A Duchess carrying out night Navaid train experienced CFIT not far from Kadina about 10-12 months ago and both instructor and pupil survived with severe embarrassment.
I feel the pilot may have "chanced his arm" on getting a crippled airplane back to the home base, but the second engine failure intervened to cause the tragic outcome. It would have been interesting to see this hypothesis considered.