:::I was going to point out that the demo's intro screen could be seen in footage of the Spaceworld 97 event, but you were the one to post the image showing that earlier on this page so I guess I don't really have to tell you. XD
In any case- footage of the event matches the demo, whereas pre-event footage with the 1996 intro screen and older graphics seems more likely to be from a build given out for media coverage beforehand. As for the fan art from the event- they were drawn from memory after the artist's return home, and the comment next to ledyba even remarks something to the effect of "there was a ladybug pokemon but I don't really like ladybugs so" with the implication that it was probably not exactly right because they weren't personally interested in the design.
Here is some recent commentary from the artist, actually: https://twitter.com/dmrn28/status/1006084888712208384 [[User:Yoriven|Yoriven]] ([[User talk:Yoriven|talk]]) 21:52, 21 October 2018 (UTC)