Next scene is the duke going to the king and saying
Duke: “Your Grace, you know that my family and I have always been completely loyal to your house and the crown, but your son the crown prince made advances on my wife right in front of me, if this continues do not think that I will simply sit still”
King: “understood, I will speak to him about it”
Cut to the king beating the prince telling him not to fuck with the duke or his wife.
Problem resolved.