It sounds to me like you just need to try creating electronic music, not using generative AI. If you really have an exact idea of what the music should sound like, you should be able to realize your vision this way, and you can use realistic instrument samples if you want. It may not sound the way a person would have played it, since you can't fully replace a human performer, but it can still sound really good, and there's a huge body of video game music from the last 30 years or so to vouch for that.