→ Duncan would likely know (of) Jordan, at least the Wolfe family for sure, since they're all Dunhaven natives.
→ Thomas might meet Jordan at Chapter One, but otherwise probably no connection there right now.
→ Duncan and Calliope are the same age. idk how much the Kanes got in with DC society pre papa Kane's offing, but I am lol'ing at the idea that Duncan might have been someone that the Pembertons set Calliope up with, once upon a time. Even if not, he's a big fan of cupcakes.