the first book's audiobook is exclusively on Audible. I tried Libby through my library but no luck there, and searching generic audiobook sites just brings up unrelated fantasy stuff. It's frustrating because the narrator they got for it is actually really good – gives the ash-covered city a proper gritty feel.
What worked for me was signing up for Audible's free trial, grabbing it, then cancelling. Not the most elegant solution, but it got me listening. I'd skip the subscription if you only want this one, though. The later books might be on other platforms, but that first one seems locked down.