Not every name attached to an audiobook belongs to a writer. Some are the publishers, studios and small audio houses that commission a recording, hire the voice and put the finished file into the world, and Mumble Media reaches our catalogue in that capacity rather than as an author.
We hold no dependable public record of the house behind the name, and we would far rather leave a gap visible than fill it with plausible-sounding invention. Small audio publishers seldom leave much of a trail: no press office, no archive, sometimes not even a website that outlives the catalogue itself.
What can be said honestly is that the credit is real and the work is here. In cases like this one the recording is the only evidence worth weighing, and it is evidence a listener can assess quite as well as we can.