May peace be with you
Without commenting on Lesley Hazleton's book(s), such evidently remarkable detailed stories are found in the works of Islamic historians, Ahadith et al and
not the Quran. There are many such stories that many readers would find troubling, but they are not Quranic.
Such stories are
not historical facts but unproven hearsay.
There is absolutely no warrant in my humble opinion, for any author or writer (no matter who that is) to rely on such stories written decades / centuries after the death of the prophet by fallible human beings in a sectarian, political milieu and present them as facts.
Please see below
[1] IBN ISHAQ'S SIRA OF PROPHET MUHAMMAD (pbuh)http://quransmessage.com/articles/ibn%20ishaq%20FM3.htmIf the desire remains to probe the story that you mention regarding the 'ALLEGED' massacre of Banu Qurayza further, I would personally recommend the following scholarly article as a start.
[2] New Light on the Story of Banu Qurayza and the Jews of Medina - By W.N. Arafat, From Journal of the Royal Asiatic Society of Great Britain and Ireland, (1976), pp. 100-107. http://www.haqq.com.au/~salam/misc/qurayza.htmlHowever, please be aware that from a Quran's perspective, such stories written by fallible men, often centuries after the death of the prophet are irrelevant.
I hope that helps, God willing
Joseph