I don't have much to say about the presence of William Marshall among the poker players on the Lauren Belle. He may not have had much to do compared to some of the other participants, but he certainly had presence.
There are a few TV Westerns in which he had single-episode roles - 'Rawhide', 'Bonanza', 'The Wild Wild West'. But if I were to make any connection for him, it would be to his role as Judge Marcus Black on the short run of 'Rosetti And Ryan'. His gambler could have been the founder of that family tree.
Of course, I could take it even further than the late 20th Century in a way that would make the two hearts of a sci-fi nerd beat faster - this family tree could stretch on for a few centuries more, culminating in Dr. Richard Daystrom in the 'Star Trek' episode "The Ultimate Computer".
I'm not sure I'd want to add the Cartoon King from 'PeeWee's Playhouse' to that lineage.....
And then there's the crazy dream that somehow there was a trans-universal crossover between Toobworld and the Cineverse, and there's some sort of connection between Marshall's gambler and his most famous role - that of "Blackula"!!
But that would be wrong....
Happy Trails To You!