For want of a less ironic word: hubris.
‘This book will challenge the dogma of [insert cultural tradition]’ is a claim that can only fail. You can critique, create a parody of or out right mock a set of beliefs. You seriously have your work cut out to challenge it in a meaningful way and your material needs to be better known for your novel to make any difference.
Particularly in this case, people lose sight of the shear breadth of Christian thought and belief. The source material for this book are The Books of Enoch’. They are wierder than Revalations, Daniel and Ezekiel put together. For the Ethiopian Orthodox, they are canonical and for many other branches they don’t even count as Apocrypha. I suspect most Evangelicals have never heard of them, or of Lilith for that matter.
How The Whale Became (Ted Hughes) probably had more impact.
By coincidence, I just picked up Canticle for Lebowitz in a local bookshop. Your post feels like intuition confirmed. Unfortunately, the ‘read it at the end of the sequence’ proposal falls. I may try The Road afterwards and compare notes.