There were submarine episodes, yes, but the actors surprised me:
Joe Maross ~ The Little People; Third from the Sun
Jack Warden ~ The Mighty Casey; The Lonely
H.M. Wynant ~ The Howling Man
Mary LaRoche ~ Living Doll; A World of His Own
John Close ~ Shadow Play; A Nice Place to Visit
Perhaps I'm strange that this occurred to me as I watched the film on THIS channel.
(W)hat are we without our dreams?
Making sure our fantasies
Do not overpower our realities. ~ RC
That doesn't make it a connection.
To prevent any connections by your definition, then every actor can only ever star ina single film/show.
Just because an actor is in one film, then later is in a different film playing a completely different role, is not a connection between the two shows.
Having an actor in a role, show up on a different show playing the SAME CHARACTER.. that would be a connection. Like when Agent Kensi Blye (played by Daniela Ruah) of NCIS: LA shows up and takes part in an episode of Hawaii 5.0
THAT would be a connection, establishing that both NCIS and Hawaii 5.0 are in the same fictional universe/franchise.
Hell Your example is even worse.
Sometimes a certain director/producer likes working with certain actors that they've worked with on past projects. Thus the same pool of actors keep recurring in additional films by the same director.
Look at James Cameron constantly reusing Bill Paxton (Terminator, Aliens, Titanic), Michael Biehn (Terminator, Abyss, Aliens), Jeanette Goldstein (Aliens, Terminator 2, Titanic) Sigourney Weaver (Aliens, Avatar)
Your example isn't even that, however.
Twilight Zone was an episodic with individual short stories of a single episode, no regular cast. It was popular and had a very large number of individual guest stars for individual episodes. no recurring roles. All your actors are from individual different episodes. Naturally you are going to find cases where members from different episodes starred together in a single unrelated film elsewhere. It's neither unusual, or all that interesting. No doubt you can find other films which has multiple cast members that at some point had starred in a certain series as a guest star in individual episodes.
Nothing unusual at all.
I joined the Navy to see the world, only to discover the world is 2/3 water!