I will assume that you are not in the US.
If you are somewhere with no licensing requirements, building codes, permits or inspections, then there is probably not much you can do other than hope for the best.
There might be a process to halt unsafe work, but that depends on the situation as well as local laws.
You can consult with an attorney if you have some basis for legitimate concern that the structure will be unsafe.
In the US, there are about 4 different ways to build a pool.
1) Concrete.
2) One piece fiberglass.
3) Vinyl liner with galvanized steel or polymer walls.
4) Fiberglass wall panels with a concrete floor.
For vinyl liner or fiberglass walls, the walls are about as thick as the panels that you are showing in the pictures.
The panels have structural side edges that provide strength as well as a concrete footer and anchors.
It looks like the pool might be fiberglass wall panels with a concrete floor.
At this point, from what we can see, I don’t see any imminent threat, but I also can’t say that it will be fine.