I know one of the co-creators (Simon W) is quite active on HN :)
Simon wasn't a cofounder. He was an early employee/intern for LJW though. Perhaps the first person other than Jacob or Adrian to work on it.
Wikipedia says Jacob was hired shortly before Simon's internship ended though. Not sure why you are trying to imply that Simon wasn't a co-creator.
https://www.quora.com/What-is-the-history-of-the-Django-web-...
In general when an intern works on something before you get there, and then you do all the real work, the intern doesn't get co-creator status.