The entry was originally a webcomic ebook. The librarian edit log doesn't show when the ASIN was assigned, whether before it was changed to kindle edition or later. However we still can see who assigned the ASIN. Perhaps you are right there regarding the source of ASIN, since it was done by member, not Amazon bot. I will leave it be then.
https://www.goodreads.com/book/show/4...
and
https://www.goodreads.com/work/editio...
(I don't think the Kindle edition is a valid one based on the librarian's edits)