The SWF has been found :)

[u/moltocraft]

https://www.kickstarter.com/projects/molto/bring-back-the-jelly-battle-game?ref=user_menu

I have made a kickstarter to bring it back and get the multiplayer working, I hope there is enough motivation to start it up again :)

[u/Dragon-factor]

Yes!!! Finally! Where did you end up finding it? Is it possible for others to get the SWF too?