Hi MrManager, welcome

(Great name, BTW; did you ever watch Arrested Development?)
I haven't heard the specific phrases "Preliminary statement of the financial state of the marriage" or "Written storybook of the marriage" but I have some guesses of what your L means, based on what we went through (briefly, my husband had to get a L ~5 years after the divorce because his kids' mom was restricting his parenting time).
When "lawyering up", if you and you L think that this might go to court, there is a phase that happens along the way (often after the other party also gets a L, but before going to court) called Discovery. That's where both sides disclose evidence so the other side isn't surprised by a bombshell. So, putting together financial data and sharing it with the other side often happens in discovery.
You sound like you're before that phase, though, so perhaps what your L is going for is "list the assets of the marriage and who owns or has responsibility for them" -- could be credit card debt, mortgage, car title, school loan, bank account, stuff like that.
I would lean towards it being more option 2 than option 1 (discovery) at this point.
So, you could list out those items in a spreadsheet: name of item, $ amount of item, owner of item. I suppose if you guys have any big ticket items that may cause conflict (vacation home ownership? boat? etc), list those, too.
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OK, written storybook of marriage... again, haven't heard the specific phrase, but it sounds like your L wants a timeline of how things went down in your relationship. When/where did you meet? When engaged, and for how long? How early did conflicts start, and do you have documentation (emails, texts) of them? Who raised issue of divorce first, when? Are you living separately now; when did it start (hint, don't move out yet, as long as it's safe to stay...) When were your kid(s) born?
Does that kind of make sense?
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Let us know how else we can help you! And, let us know more about your kiddo when you can -- age, how they're coping, etc.
Cheers;
kells76