Here’s a peek behind the curtain: Mike and Claude do their own research for the individual shows, though Mike did the initial setups for the dates. So he’s the one who figured out what happened when, and then they each do the deeper research for the episodes they record.
So Mike probably had no idea that there was a familial connection to this episode for Claude. For what it’s worth, neither did Claude, until he started looking into the story of Nathaniel Gorham. So if Mike had been recording this episode, it’s likely that he wouldn’t have had anything to say about it other than “Oh, fun coincidence.”
We’re only sad that we couldn’t find a portrait of Nathaniel; we have no idea whether there’s a family resemblance.