Honestly I still think you will get a whole bunch of people whining if you did this. People expect guides to work perfectly and that is damn near impossible for a game like this. I can just imagine people saying "I did the sleep thing on Thursday with Mrs Maywood but nothing happened" because they don't have level 5 in sleep experience. I love the way this is built because I like to look for different pathways but the way its built also makes writing a complete guide damn near impossible especially before the game is finished. I think the best option is ti build an example walkthrough with a miniature guide about characters. Either way I think it would need to be rewritten and rechecked every update until the actual full game is finished.
I disagree, and I think you're missing the point of how it would work. If needing level 5 sleep experience is necessary to trigger a scene, that requirement would naturally be listed in the page for that scene. If it's absent, as a wiki, any(?) user could easily fill in that missing detail. The idea is to provide details about each "dot" and then let the players use that information to "connect the dots" in their preferred way. The issue you described would be much more likely to happen with a straight walkthrough, and including enough detail to prevent it from happening would take an excessive amount of work, as there are tons of ways to play through the game and each separate walkthrough would end up re-treading the same ground as others. But that's not an issue when the guide itself is just the details of each of the pieces the game is made out of.
There's also little need to redo every page with each update, as the dev generally doesn't change anything about previous days when making new updates (even to the point where major elements of the UI are missing before the day when it was added in an update). As long as each entry is self-contained, the information it has will continue to be useful in the context of all future updates, with maybe a line or two added at the end saying "this will serve as a trigger for a scene in day X". And since it's a wiki, virtually none of this is on the dev, as it will pretty much all be filled out by users. Once it's set up, the dev shouldn't have to touch it again, barring some issues with vandalism or something.
Another benefit to being a wiki is that there isn't (or shouldn't be?) anything stopping people from making separate pages for useful information some people might want to know, including any mini-walkthroughs someone might want to make, or a list of all opportunities to increase any given light's EXP, or something like that.
Overall, I think a wiki is one of the best ways to handle this, and shouldn't take much of the dev's time at all. ...Presumably. I actually don't know how much it takes to set up the basics of a wiki, but once it's there they should be able to just forget about it.