Ineffectiveness of divorce by a delegated person in a way that is not directed in the Sunnah

Q: Twelve years ago, I delegated someone to divorce my wife as directed in the Sunnah (whatever is reported from the Prophet). Is this permissible? Since she is not married now, is it permissible for me to take her back in marriage if she agrees to marry me?

(Part No. 20; Page No. 55)  A: If your Wakil (legally accountable person who acts on behalf of another for a specific permissible matter) divorced her as directed in the Sunnah and her `Iddah (woman's prescribed waiting period after divorce) elapsed and this was not your third divorce, you may marry her with a new contract, a new Mahr (mandatory gift to a bride from her groom), and with her consent. If he divorced her in a way other than that directed in the Sunnah, it is ineffective because you did not delegate him to do so. Moreover, if your Wakil has not divorced her, she is still your wife and you may reconcile her and take her back home. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.