She's most likely going to get a public execution the Duke literally said he didn't acknowledged the letter meaning he is throwing Christa the daughter he "loves" away to save his ass.
But I think he knows even then his reputation will 100% decrease because of her execution. (Idk I'm just saying things)
Whatever happens, it sounds like a win-win situation.
I read spoilers and Heinry gonna make her die by faking her suicide with a letter saying something like "it's your fault", that's why rope is around the neck.
I get that heinry is threatening the duke with Christa’s life but what is the significance of the red rope around her neck?