MC goes berserk over the the fact that some guy was going to give him a cuckold. However another of the MC's wife (long story she lost her memories but MC knew who she was) whom was to be engaged to another guy but the MC didn't show any resistance, it just so happened by his luck the wife refused to go through with marrying the other by her own choice.
MC's enemy has held some of his family hostage/prisoner for around a decade. Enemy representative that was sent threatens MC to swap one of their captured spies with one of MC's wives but somehow (honestly seems like an ass-pull used to prevent the MC from bowing to the enemy) MC figured out that the Enemy's goal is to convince the MC to cooperate with them so they won't harm any of his family. So he has his subordinates beat up the enemy representative without consequence. Not long after an enemy spy is discovered in MC's camp and the spy took his kid hostage but now MC is afraid even after he just confirmed that the enemy won't hurt any of his family.
He was willing to just abandon his wife and let her marry another guy.
He was also willing to let another plan fail because he just doesn't take the necessary action to prevent that, it's the other or a third party that ends up doing things that lead to his advantage and that is pure luck and it has nothing to do with the MC, he doesn't plan it.