- "That hag just killed your brothers" when talking to Mayrina after killing the hag
That's actually in the game, the catch: you need to tell Mayrina before the Hag teleport her in the cave.
Exactly, you "need" to tell Mayrina BEFORE, what's stopping you from telling after?
- "You're doing the same thing as Wyll, you've got no right to talk Shadowheart" about Shadowheart talking about Wyll and his secrets
She's not keeping secrets, she reveals things on a need to know basis.

Whatever that is, it's still calling the kettle black but that's besides the point it's about not being able to tell the characters what you actually want to say
It really is like Skyrim dialogue.