Naturally it pays to bear in mind that Ven. Nyanavira has read this book through the prism of his experience with the Buddha Dhamma, and he has made his interpretations using such a 'dialect' if you will.
As you quite rightly state binocular, none of your literary teachers were Buddhists, and therefore they wouldn't share Ven. Nyanavira's interpretation, but would have their own (or rather someone elses) that they had gained through their own formation of things.
When it comes to books and film and the whole English dissection of these things I think there is almost never a black and white answer. They don't call 'interpretations' interpretations for nothing after all and I think that's the beauty in film and literature - You can read what you like into it, and different people will see different things in art, based upon their own predilictions.
As it happens I have found Ven. Nyanavira's interpretation of Kafka, along with other existential fiction writers to be quite useful, but others may not
"For a disciple who has conviction in the Teacher's message & lives to penetrate it, what accords with the Dhamma is this:
'The Blessed One is the Teacher, I am a disciple. He is the one who knows, not I." -