Complex sentence: The accuracy of the book has been questioned due to minor inconsistencies in Wehrmacht procedures or uniform details, resulting in claims it is an outright hoax, or an historical novel in the vein of "All Quiet on the Western Front".
Split into simpler sentences: The accuracy of the book has been questioned due to minor inconsistencies in Wehrmacht procedures or uniform details. Resulting allegations have ranged from its being an outright hoax to simply a historical novel in the vein of "All Quiet on the Western Front".