In my view, there is no direct implication in this chapter of cannibalism. ‘Where some must die that others live’; it can just as easily be argued that there isn’t enough food to feed everyone, so some have to lose their lives either by the ‘sword’ or ‘chance’, so that what food does exist can sustain the strong, the wise, the young, etc.
'"Where there is a chance for life, the strong shall take that chance and leave the certainty to the weak…
“Let us pray we never have to use the sword‒ (clear implication of a sword, but none of a cook pot)
This tells me that those too weak to survive on their own, but were judged to die for the group were put to death, but not necessarily eaten. One strong, condemned to the same fate, could choose either the sword or his chances on his own. One who was strong would certainly provide a more robust sustenance to the survivors than one who was weak, yet he is given a choice instead of a death sentence. Why is this so? No one would willingly accept starvation if they could be euthanized instead. A person who is ‘weak’ would have no chance of surviving on their own, therefore, instant death would be what is most merciful to the weak. For the strong, they may yet survive on their own, so they are given the choice of the sword or chance as an exile.
In some other primitive societies, options and moral decisions such as these generally aren’t taken into account in bleak survival situations, and ritual sacrifice of children, the young, a class within the society, etc. are readily chosen as prime meat for the priests… yet in this Kolbrin chapter, it is not so. What is considered is an ethical (necessary) euthanasia, not allowing starvation if it can be helped, a quick death to those whom cannot be sustained, and a choice of exile or quick death for those who are deemed not most essential to the future, but who may possibly survive on their own.
Thus, cannibalism may be extrapolated here as a stretch, but it is by no means clearly indicated, nor would it be ethically consistent with the rest of the Kolbrin e.g. the stories of Yosira, and elsewhere, etc.
(Example, emphasis mine:
"He also laid a curse upon women who baked their new born children and ate them because of the barrenness of the land…
"Therefore, the land became stricken with a great plague. Since then never has anyone in the enlightened lands eaten the flesh of man or woman…
“So Yosira released the man who was bound upon the place of sacrifice, but he was not yet whole. Yosira also cursed all those who offered the Hestabwis as a sacrifice to their gods; since that day no man of the Hestabwis was ever slain upon the altars.”
– The Kolbrin, Book of Gleanings, Chapter 12)