The addition of another condition in the Blood Soul Contract, the matter of hiding information from them, would've spelled Daniuis Alstreim's doom.
Fortunately, Princess Isabella's timely appearance that was orchestrated by Davis through Nadia's concealment helped in that hall helped save Daniuis Alstreim from being subjected to more conditions on the Blood Soul Contract. He instantly agreed to the contract, and the end result was that the Blood Soul Contract's binding totally became useless on him while Ancestor Xanbas Goldsky and Ancestor Tirea Snow would have to abide by their promises and bring Daniuis Alstreim's children back to the Alstreim Family.