hickey is a reflection of his surroundings. hickey is a cog in the imperialist machine oppressed by its structures and forces who conceptualizes a word, not without those structures and forces, not free of them, but which may serve as a blank slate for him to be the enactor of said forces rather than their victim. his vision of the arctic and the tuunbaq is one formed by a colonialist manifest destiny. the arctic is an "untamed wilderness" and the netsilik are "savages" and he, as a poor gay white man, can easily rule over them because they're too dim and phrenolpgically inferior to realize that he is the chaffe of white imperialism. it doesn't matter that he's from the bottom rung of the british ladder because that's a ladder that starts ten miles up from where its victims live. and he is punished for this hubris and his additional fundamental misunderstanding of the tuunbaq with his grisly death.

crozier survives and stays behind because he is the one and only man on terror or erebus who gave up england. he truly left it behind. expunged it. hickey could not do that. hickey had no interest in doing that. hickey saw before him an opportunity to build a new england in which he was at its head instead of under its heal. hickey got snapped up and eaten by a force he could never hope to understand but thought to tame.

Also I love me some medieval bestiary symbolism, and this is one of my favorites:

The stag is the enemy of the snake. When the stag discovers a snake, it spits water into the hole where the snake hides, draws the snake out with its breath, and tramples it to death. If the stag is ill or old, it draws the snake out of hiding and swallows it. The stag then finds water and drinks large amounts of it to overcome the poison, and is renewed. When the stag is renewed it sheds its horns.