Does a Waliy know the Ghayb?

Q 1: Allah (Exalted be He) states: "(He Alone is) the All-Knower of the Ghaib (Unseen), and He reveals to none His Ghaib (Unseen)." Except to a Messenger (from mankind) whom He has chosen (He informs him of unseen as much as He likes) Can a Waliy of the messenger's Ummah (nation based on one creed) succeed him in knowing the Ghayb (Unseen)?

(Part No. 2; Page No. 182) A: Allah (Glorified be He) has decreed that the knowledge of the Ghayb is exclusively His, for He states: Say: “None in the heavens and the earth knows the Ghaib (Unseen) except Allâh” He has not excluded any one except his messengers (from mankind) whom He has chosen, at that time. He (Exalted be He) informs him (the messenger) of whatever He wishes of the Ghayb. Allah (Exalted be He) states: "(He Alone is) the All-Knower of the Ghaib (Unseen), and He reveals to none His Ghaib (Unseen)." Except to a Messenger (from mankind) whom He has chosen (He informs him of unseen as much as He likes), and then He makes a band of watching guards (angels) to march before him and behind him. Therefore, whoever claims amongst the communities of prophets and messengers to know Ghayb, is a liar.Moreover, whoever claims that any of the Awliya' (pious people) or righteous who follow the creed and teachings of messengers has knowledge of Ghayb, will be a liar in error. This violates the Qur'an and what has been authentically reported from the Prophet (peace be upon him) in Hadiths which indicate that Allah Alone has knowledge of the Ghayb.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.