Some time ago, I met an English speaking anime producer and introduced him to my favorite anime. We figured out that it is severely undervalued by the market based on the mismatch between its cult following and actual fanbase size (you know, very few anime have hours long YouTube essays dedicated to them), so we decided to start a spiritual successor to both capitalize on an underrated idea and indirectly advertise the original show. I had an idea to develop a video game first, to (maybe) later adapt it into actual anime.

My plan is as follows:

1. Attach some JP seiyuu and animators into the project through the producer's connections
2. Develop a gameplay demo & trailer with them
3. Drop it on a crowdfunding platform, attract people with their favorite JP talent
4. Raise enough $ to cover the entire development cost, including developers more competent than me (lol)

Now, there are two problems I'm facing:

1) the guy disappeared. He is probably just too busy - previously, he couldn't reach out back for weeks, and he also couldn't meet the animator who connected us too for a while. However, the fact is, we haven't been in touch for a while. Probably the best way to get him back is to throw money at him, but
2) I need to pay the producer, seiyuu & animators even for a demo, and unfortunately can't afford it personally. I probably can generate some assets with AI but posting it as demo is a suicide and also loses the whole seiyuu + animators selling factor.

What do I do?
I have a great investor friend who can help with much more than just money, but he doesn't have bandwidth for me right now.
A realistic option would be to develop a demo (even with stupid AI) and contract a publisher, but I'd rather take money from some private investor to retain more control over the project.

Producing a game is risky business.

It sounds to me, like you think you have the great "idea" to produce a game that basically profits from an existing fan base. Add some actual professionals and the product will sell.

That's not an idea. It is business as usual for actual existing professional publishers and studios. Success of the original IP does not automatically translate into success as a game. Your youtube fans that nitpick over the source material might not be the ones that would even play the game. Or they would be the ones ripping the game apart for it's flaws.

Chances are, that someone already has the rights to the "underrated" IP for creating games, even if none was made yet. And you do need those rights to create material based on that IP.

But maybe I misread and you only want to create a "spiritual" successor. Like gotta catch them all principle and make a game out of that. That means the risks are even higher. Just because the original has some die hard fans years later does not translate into success of a similar concept in a different media. Or a new franchsise that copies core ideas.

What do I do?

Do not throw away your life savings onto such a high risk project. And do not go in debt for this. You described some red flags here about your future business partners.

If you have budget to spare you can fool around with it, of course. If you aim for crowdfunding, that is a long process anyway. Maybe you can recruit people from the fan base. Fan games are a thing.

Can i recommend you talk more about the original anime and the game idea? perhaps you might find here artist and programmers willing to help at least with the demo until you can start a kickstarter/crowfunding campaign and use then that money to hire artists. 

IDK, is just an idea.

BTW. I don't recommend using AI if you are not artist or programmer, talking by experience using SD 1.5.  (control net and Krita + krita ai diffusion) and chatGPT/Geminy in programming.  Trust me, AI don't replace the professional it just a tool for the professional to use. You might be able to create a small prototype with AI but if it scale, AI alone become useless.  

https://opengameart.org/