While Arianna was busy dealing with her own business, Maxim was also busy trying to make things easier for not just himself but for Arianna as well. After spending this time living with Arianna like husband and wife, he didn't want to hide anymore.
Maxim wanted to show himself to the world but that was risky and he didn't want to put her under any pressure. But as a man who proposed already, he wanted her family to meet him finally.
He wanted to officially propose to her family, that way they will know that he wasn't some wild man and he was serious about Arianna. He didn't tell her about it as he wanted to surprise her.
He knows that she will not say anything about him as long as he didn't give a go ahead. So, Maxim sent his men to look into the whereabouts of the Duke and Duchess, Arianna's parents as he wanted to go to them and meet them.