Just wrote a response to essentially this question in here:
https://www.mobileread.com/forums/sho...24&postcount=7
TLDR; is - nope, because Amazon sees it a as an asset to tightly control their reading environments, and they dont like them to be fuzzed around with.
The corresponding files are not only highly "gated", they also respond quite fast to devs trying to get a sense of them and changed them consequently in the past.
Also their most current reading environment (parser) is closed off for anyone but Amazon to use. They already have marketed some of the features in there as "Amazon exclusives" (you have to let Amazon create the ebook file itself to make use of them - no way around it).