Armand has chosen to interpret his purview of 'maintaining the heirarchy of Acryn's estates' as 'ensuring that competent people are in charge'. Therefore, his brainwashed aunt has to go. He intends to do a favour for the Circle of the Broken Wing, as a coup within the family will rely on their support. This way, he can hopefully organise a vote to make Walter Head of House.

Beforehand, he also plans to find someone to construct him a new heart - perhaps his husband will be willing to strike a bargain? After all, as much as he intends to keep his word with the Traitor, there's no way that pickpocketing is acting in the spirit of their deal… nor does he intend to allow her to wield that sort of power over him.