Complex sentence: Martel pointed out that he could not have stolen from a work he had not at the time read, though willingly acknowledged being influenced by the review of Scliar's work, and thanks him in the Author's Note of Life of Pi.
Split into simpler sentences: Martel pointed out that he could not have stolen from a work he had not at the time read. Instead, he willingly acknowledged being influenced by the review of Scliar's work, which is why he thanks him in the Author's Note of Life of Pi.