When you enter the longhouse during Victory, you’ll have a number of dialogue options during the cutscene which follows, depending on what you did with King Charles.
What to Say to Toka if You Spared Charles…
If you spared King Charles, after the scene with Count Odo, Toka will ask Eivor what they think Odo will do from here. You’ll have three dialogue options:
“He will look for Charles.”
“He will focus on Paris.”
“I do not know.”
What to Say to Toka if You Killed Charles…
If you killed King Charles, after the scene with Count Odo, Toka will ask if it’s wise to trust Odo. You’ll have three dialogue options:
“Odo has honor.”
“It is never wise to trust.”
“We cannot know what the future holds.”
In both cases, it doesn’t matter which of these options you choose, as the quest will play out the same since the major decision of killing or sparing Charles has already been made at this point. All that will change is the response from Toka, in a minor way. Toka will state that she’ll have Pierre watching Count Odo from now on, and after a farewell scene, the quest will end.