These don't seem to go far. Boat D contained Hokan Steffanson, a Swedish businessman who lost a painting that he claimed at $100,000. Boat A contained tennis champion Norris Williams. No strong leads; I think it's "dead or alive". Turns out that without seeing this year's meme I correctly pegged the three alleged opponents of the Fed in this thread: Astor, Guggenheim, and Straus.

A bit better than my theories in this cascade is a reading I give elsewhere in this thread. Who lived in the movie (what man)? Astor, in the spirit realm, presumably. Why is this relevant? Astor was reported as dying. Opposite is true. Does this mean Astor (or a different opponent) was permitted to live by forging another identity? That could be followed up on.

Further, "Numerous notable and prominent people of the era, who held tickets for the westbound passage or were guests of those who held tickets, did not sail .... Those who held tickets for a passage, but did not actually sail, include Theodore Dreiser, Henry Clay Frick, Milton S. Hershey, Guglielmo Marconi, John Pierpont Morgan, John Mott, George Washington Vanderbilt II." Emphasis added. Q has special focus on the Vanderbilts' alleged Satanism.