@darthmongoose Exactly this.
I deal with this a lot because my storytelling basically focus on very complex lore that sits in my head of which I only want to give hints. I struggle a lot with wanting to reveal more about all this backstories, but I want the reader that is interested in it to take it as a game. To really participate in the metanarrative play, to wonder and especulate. I know it is a massively difficult task but is also a challenge I'm daring to face, and what works for me is having two very close persons that know almost everything, and maybe one person who you give some extra hints. This way you will have feedback about it all making sense, and also the viability of knowing and dissecting all of the inner folklore of your work.
(By the way congrats on Errant, I think you are doing great)