Re-think your format:
If you keep writing 'situations' but you aren't sure where they are suppose to go next, maybe the situation itself is the story, and it's better suited for a short-format that explores that moment, leaving the possibilities open for the reader to imagine.
This doesn't sound like what you want, but maybe you are a great short-story writer who isn't benefiting from the rules of a longer format. Maybe there are other formats that better suit your writing (episodic, for instance).
Re-think your outline
I wouldn't attempt to write any narrative without knowing the major characters' arcs, for me that is the story, the 'plot' is just stuff that happens to help push them along their arcs.
If I know my main character is on a negative arc, their timeline is a series of small positive steps followed by a big drop. 3 or 4 of those up-up-up-DOWN patterns and that character's arc is more or less solid. I know whether their next scene is about lifting their hopes or crushing their spirit.
See Kurt Vonnegut's Shape of Stories lecture, and Robert McKee's Do Your Scenes Turn for well-known examples.
With 2 or more main characters – each with their own complete arc – you can have A-Plot/B-Plot, used in TV and film. Break away to another location, and another concurrent story – related or not, maybe even a complete tonal shift.
Sub-plots are a step down from that extreme. A sub-plot is a different story happening to the same characters. It gets updated in spurts, usually during the lull of the main plot. Again it doesn't have to be related or the same tone. The stakes can actually be a counterpoint to the main plot.
A step below that are the slice of life situations that provide worldbuilding and context. Greek Chorus and Maid and Butler dialog use simple, undefined characters for exposition, but they can also provide the broader viewpoints of the world that your main characters wouldn't know or discuss. Watchmen uses vignettes of very ordinary people to show the humanity that is lacking in the main characters.