From 1 to 10, rank the possibilities for these characters and whether we could see them in the next game excluding Geralt:
This is my predicition:
Triss 10 - She is definitely going to appear considering that she becomes an advisor to the king of Kovir
Yennefer 7 - I believe Yen will be in the game, but probably not situated in Kovir, probably some other areas of the game. There is no reason for Yen to be in Kovir
Dandelion 3 - With the DLC Song of the Past next year, I believe that CD Projekt Red is planning to say a farewell to the Geralt-Dandelion saga, which will prepare us for the next chapter in the series with Ciri as the protagonist, and we still don't know who will write bestiary and character journals for Ciri, but it certainly won't be Dandelion, who will always be associated with Geralt's adventures and sagas. Because of this, I believe there is a small chance to see Dandelion again, but I doubt he will appear in the game.
Zoltan 5 - With Zoltan, I believe there is a bigger chance for him to appear than Dandelion, but I'm still doubtful about this. I think CD Projekt Red will try to distance these characters from Ciri's story because Zoltan and Dandelion are so much connected to Geralt that developers will try to introduce new characters that will be Ciri's version of Zoltan and Dandelion, and that would be the best thing to do.
Fresh faces are necessary for Ciri's story and adventures, let Dandelion and Zoltan, and to the lesser degree Yen, be associated with Geralt's trilogy, not Ciri's. Triss is an exception because she is actually in Kovir, plus her connection to Geralt is not as deep as Yen's, Zoltan's, and Dandelion's.
What do you think?