I loved the first so much I added this to my Steam wishlist when I saw it was being made and just noticed it was canceled. I absolutely don't want to try and push your hand into finishing it if it negatively effects you, but if you released it as open source with your intentions of what you wanted it to be (your description is already a pretty solid high level overview) and it would be people that are familiar and appreciative of what makes it an Orbo game working on it.
If it isn't included in the reasons you were trying to avoid when you had to cease work, you could act as just a director for it and manage the repo instead of a fork working to finish it. I know if new assets are needed that makes it harder because that's harder to make consistent, but it sounds like you have a good majority done. People seem to have enough love for this that they'd probably be happy to contribute to finishing it with you maintaining rights to the assets and selling the game on Steam. People would be able to build whatever is provided with the source for free, but the pre-built convenience and features like trophies on Steam adds would lead to players almost always just buying it, and no one else would be able to sell it unless they changed out all the assets. It might be nice to give any notable or possibly all contributors free keys. Or you could just release it for free on itch with the option to donate. You're already giving it away for free because it isn't complete, but this way people that love it would get the game they want, it'd be the game you imagined if you oversee the work on it, and you could get paid for the tremendous amount of work you put into making most of it.
I have quite a bit of experience making games and would be happy to help. I'm probably not good enough to finish it up to expectations by myself, but I absolutely can do a lot to get it there.
