Dang, that's dark xD
I like the idea, but I'm not sure how well it fits into the plot. It would have been much easier for the king to just execute Crow in prison, rather than send him on a doomed mission, so I think he would have just done that instead. Also, Crow's father doesn't know who his son is. He left before Madeleine gave birth. Crow only knows his name (and that he apparently looks quite a bit like his father), but not his face.
Wars are expensive, so the king isn't trying to avoid one for the sake of his people, but rather the sake of the contents in his vault.
It would be interesting to throw something in later, where maybe Crow meets his father when they get back to the kingdom. He tells him who he is, and his father then wants to try and have him killed before anyone else finds out he had a son with a peasant woman.