If an individual contacted by a confidential intermediary consents to the disclosure of any information, the confidential intermediary shall obtain the written consent of the individual witnessed by a notary public. The written consent shall specify the nature of the information to be disclosed. If a confidential intermediary obtains written consent under subsection (a) of this section, the confidential intermediary shall disclose the information specified in the consent to the individual who applied for search, contact, and reunion services. The confidential intermediary shall disclose only the information that has been authorized by the written consent.