Deep Space Nine is a Space station belonging to a Federation member world, administered by Starfleet. a Klingon ship should no more be able to visit DS9 then a Dominion ship could visit it dureing the Dominion war.
The Klingons aboard the station are eaither diplomatic staff or civilians.
Please tell us the licensing gods were kind and you were able to procure the DS9 theme song for the next Featured Series!
I would settle for the Visitor Suite and the theme from The Inner Light for non-combats like Scan 5 exploration and First Contacts. They're both almost certainly easier to license than the main themes.
The Visitor suite would evoke what is arguably DS9's greatest episode and, I think, serve as a reminder that this is a place that Sisko was but isn't there anymore except in spirit.
In general, I'd almost say that the main themes are a little too "on the nose" to use from an artistic standpoint. It risks taking you out of the moment by being TOO awesome. But the better episodic scores would hit nice emotional touchstone moments. And I'll freely admit the worse episodic scores make me want to hit mute... But the really good ones are nice because they're the kind of music that tells a story.