Looks like one of Marshall's big booster and some of his family passed away in an accident near the Bahamas (seems they were flying through the Bermuda Triangle)
BBC News - Tributes paid to air crash coal tycoon Chris Cline
https://www.bbc.co.uk/news/world-us-canada-48898057
BBC News - Tributes paid to air crash coal tycoon Chris Cline
https://www.bbc.co.uk/news/world-us-canada-48898057