Refuse her offer

Lana: Look guys... As much as I love my father and you all but... Honestly, we cannot sacrifice the galaxy for only a few people! Think about it! What would they say when we returned to them with the news, "look, sorry, but we have unleashed an unstoppable power upon the galaxy, which happened to devour it, but at least we are alive, as long as she lets us live here!". I'm sure the reactions would be priceless, but better not try it!

Drek: See?! That's what I was trying to explain!

Ranvi: Yes but...! Ah... you are right... We cannot let her get out of there...

Lana: Good, so we are all in agreement!

Abeloth (infuriated): What?! How dare you?! You must free me or I will unearth your corpses upon my return and bring you back to life only to cause eternal suffering to you all! Free me now!

Lana: Sorry, but not gonna happen! Maybe we aren't the ones to prevent your resurrection, but we can certainly leave you imprisoned for now! Let's go guys, we better leave this place, the sooner the better!

Drek: I concur! I'll get the ship ready for launch.

As you start walking back towards the hangar Abeloth keeps sending all sorts of threats to you, but you ignore them. Before leaving the room, Ranvi turns back and takes one last look at the controls, which might be able to alter the course of galactic history. A few thoughts pass through her mind, before she goes after you two and enters the ship alongside you. Drek flies out of the space station and recalibrates the system, still connected to the compass, to show the path out of the cluster and away from the station. The way back goes uneventfully, the autopilot avoids all the black holes again, but this time Drek could remain seated and watch the ship do his work.

Lana: What a place it was...!

Drek: Yeah, just imagine, we were so close to be able to doom the whole galaxy!

Lana: Don't even say it, what if the separatists discover the place?

Drek: We better not tell anybody about it, nobody should know of the existence of the station!

Ranvi: Mother Talzin sent us there to find something, she should know the truth!

Lana (after looking at Drek in silence): Ranvi, maybe we shouldn't...

Ranvi: What...? She trusted us to go there, she deserves our trust to be put in her in return!

Drek: This might sound badly but... We cannot be 100% certain about the intentions of Talzin! If we handed her the power to doom the galaxy at any moment, she might one day do it herself!

Ranvi: How could you say that?! She is my mother, she would never harm the galaxy! She has her views about the Jedi and Sith, true, but she would never cause such chaos!

Lana: Ranvi, I think Drek was trying to point out, that Abeloth herself said she will be freed in about 60 years or so... Maybe if we spread the news about this place, we would cause her return!

Ranvi: You cannot know that! Maybe if we told mother about it, she would be able to prevent that from happening!

Lana: If you insist on telling that to her, so be it... You know her the best among us, if you trust her, so will I.

Drek (as you are both looking at him): What? Okay, tell her about this place, but don't tell me I haven't told you it was a bad idea!

Ranvi: Thanks for both of your consent, she will be pleased she had placed her trust well in us!

Upon returning to Dathomir, Ranvi rushes to Mother Talzin. Along the way, she meets Merrin, a young Nightsister, she had grown fond of some years ago. She is around 10 years old, but ever since she can speak and walk, she tries to use magical spells.

Merrin (raising her hands to hug her): Ranvi!

Ranvi (hugging her): Oh, Merrin! Long time no see! You have grown so much! How is the spell learning goes?

Merrin (saddened, using a spell to form a ball): I can still do only a few... I'll never know as many as Mother Talzin knows!

Ranvi: Don't give up Merrin, you'll learn them in time, I know! You are going to be a great Nightsister, you are still young, full of potential! And don't use Mother Talzin as a standard, she is the strongest here! Speaking of whom... I have to hurry and talk to her in an urgent matter! Be well and good learning!

Merrin: Bye Ranvi!

After this short conversation, Ranvi finds and tells Talzin everything. She was indeed pleased you told her about the station and decided not to mention it to anybody, for the same reason as you were bringing up, such powerful weapons are better left unknown. But she was most distressed about the vision of the invasion of Dathomir.

Talzin: I have suspected such a thing for a very long time now... The Sith have always been a trouble on the horizon for my people. I have made some safety preparations to face them, should the time come, but it seems they will not be enough...

Ranvi: I'll be here and help you mother, however I can!

Talzin: I'm certain about it my dear, but one Jedi cannot overcome a whole invasion **** either! Maybe with a preemptive strike on them, to surprise them... Hmm...

Drek (whispering to you): Maybe not, but 3 certainly had a better chance! What do you say Lana, do we join the Nightsisters to stop the Sith once and for all?

Lana (whispering): Hmm... It would be a suicidal mission, bringing the Sith here... They would bring an army of droids, that we have never seen the like...! We should ask the council for assistance, they would certainly be glad to find and stop Sidious, even if it meant working together with the Nightsisters!

Drek (whispering): I doubt they would bring too many forces here, the war occupies them anyway. If we are left alone, we might not survive an invasion! But I'll let you decide this one, act as you see fit!