Moses wrote of his own death?
Because someone else (perhaps Joshua) redacted the Torah does not mean the Torah was not compiled by Moses. Take a modern day example, for instance:
Paul Little wrote some good apologetics books, such as "Know why you believe". Mr. Little later died and his wife, Mary, "redacted" some of his books, telling of Mr. Little's death. Does that mean Paul Little did not write or compile his books? No. Of course not.