Is there a list of the cards included in Scuttle! and its expansions?
You would expect a game inventory on the Jelly Bean website. 

Took a little search, but here’s a YouTube that reviews the Black Jack game expansion, showing all of those cards. They are:

Black Jack rule card, Voodoo Queen, Governor, Dagger, Powder Keg, Sea Serpent, Black Jack, Ghost Pirate, Grappling Hook, Black Spot, Crow’s Nest, Grog, Buried Treasure, Sirens, The Plank, Poison, and Parrot.

That should allow you to finish splitting up your decks.