That might wash if Jesus said the keys to the Word of God, but He didn’t, did He? No, He said, “I will give you the keys of the Kingdom of Heaven.”
Jesus spoke often of the Kingdom of God and the Kingdom of Heaven. Matthew uses Kingdom of Heaven, Luke uses Kingdom of God so it would seem they are the same thing.
First Jesus tells all the Apostles, then He singles out Peter later when He explains why He has changed Simon’s name to “rock”.
Scripture holds the words of God which are the keys to the Kingdom.