We're talking about the "I am a pool of water" scene right? Darkness is barely mentioned then, let alone to convey fear... the only "death" I can see would be losing himself in nature and his spirit not being able to come back to his body (like in another scene he says " am immediately struck with panic, as if, in losing hold of my seperate and individual soul ... I might find myself lost out there in the multiplicity of things, and never get back").
I don't see these kind of comprehension type questions very useful, in my class we're writing essays comparing Malouf and Wordsworth's ideas; in-depth detail is a waste of time for what will boil down to a broad 1000-word essay.