@Malikoman
@Dogmans897
From what I remember, this case was legitimately murky in the novel. I think Wendelin's father ends up explaining his end of the issue and it turns out that there was some plot with the fiance and the headman's son that ends up in a fight (with some other people), and then politics with the other headmen result in Wend's father faking their deaths by cliff and asking to marry the daughter to protect her.
But who knows if Wend's father is lying or is just misunderstanding something?
There never is clear evidence one way or another in the novel and the question goes unanswered.