I feel as though between Grey Owl and James Frey, Grey Owl is the bigger liar.
He lied about his entire childhood. He would not see the true wilderness until he was 18 years old! The press had labeled him a "full-blooded" Indian despite his blue eyes, Grey Owl never corrected this. He was not even a full-blooded Indian, let alone a half-breed. Grey Owl was born in Hastings England. His real name was Archie Stansfeld Belaney.
James Frey created a few of the situations in his book, and did lie about being wanted in three states. But atleast he lived "most" of what he wrote!