Writing a story with too many puzzle pieces missing is not a good idea. There's far too much work to be done.
When too much is missing, you have to rely on logic to fill in the pieces and that's just exhausting.
Perhaps you need to make some choices about what is and what isn't really needed in the story. That can be difficult when the story is offering more than you asked of it, when details arise of their own accord as you type and think about what comes next. I'm in a similar pinch and yesterday I asked some questions here in the forum and received lots of very good information - not all of which I will be able to make use of in the confines of the size of story I want to write. But that doesn't mean the information wasn't constructive. It was. There are certain things I can flip around and sort of lampshade their absence as part and parcel. Other things are details that simply don't have a place and will just have to be forgone in full. Ask yourself what is important to the actual story, and what really isn't, what's just stage dressing, and be dispassionate about it.
If you haven't already, you could try fleshing out the scenarios you have & from there see if one piece fits better in a different place. It doesn't have to make complete sense yet, just jumble those puzzle pieces around, see what happens. Try to be flexible & don't worry too much about continuity either.
Planning is impossible for me, instead I write stories from the heart(?), which often end up making them messy; though I'm working on being more structural. I'm not sure how to express this because I don't understand it myself yet, but, there's such a clear difference to me when I try to figure something out, meaning calculating the logical progression of how events should transpire, vs winging it. The former is torture. Of course, there must be some sort of base foundation for me to able to wing it effectively, which is what I mean with missing puzzle pieces. When too many of them are missing I need to fill in the missing ones and that is when the work drags on and on. Some stories come out clearer than others with more puzzle pieces available to me and I'm trying to be better at choosing which stories I pick that has less hassle attached to it. Sorry for the original post being confusing but I didn't intend for it to be a cry for help, just being dumb.
I would say to just keep writing, and if there are plot holes, you can plug them later on. If you're the sort who likes to write without planning, you can be sure there will be plot holes and pieces missing or out of place. However, what you write will be fresh and spontaneous. It's easy to fix mistakes later, but it's very hard to drum up that kind of fresh enthusiasm if you really hate working to an outline. As long as you're willing to go back and fix the issues, once you're finished your first draft, you'll be fine. Lots of people write that way. (Including me!) What you can't expect is for everything to come flowing out perfectly first time. Unless you are very VERY unusual. And if that were the case, you wouldn't be having a problem. So just write while the spirit moves you, and THEN fill the holes and get pieces into place.
The best ones are to write on paper all thoughts, ideas, even pieces of plots. So the overall picture will gradually take shape.
Many great writers have practiced planning. They planned how many hours a day they would write or how many pages. It helped them a lot!
I know the feeling. For me, it takes a good amount of rewriting to get myself out of this predicament.
I'm following a beat sheet. What I did this time - because I ain't spending another 12 years on a damn novel, no - was I planned it according to word count. If the first 3 chapters (50 pages) are usually requested as the sample for a query, then the inciting incident needs to already have happened within this. If the novel is 80k words roughly, then by 40k I know I better have reached the middle. And by 60k I should pretty much be leading up to the end. Then I go back, see what I have, and make a vague plan for what happens next based on that. Write some, checking against the word count as to whether pacing is ok. Then I review my plan - I don't stick religiously to it - and I alter my plan according to what I've written. This way, I have a road map but I can deviate and plan a different road halfway through. Anyway I know you don't need to follow a beat sheet. But hey, my last novel took 12 years because I hadn't a clue about structure. This time, screw creativity and being artsy fartsy, sorry - I'm following the damn beat sheet! If I have a good reason to deviate, I will, absolutely, but if I don't, then I might as well follow the beat sheet as a tried and tested structure. Once I have structure down, then that's the time to experiment. Until then, beat sheeeeeeet!
