I had a short look at the files. The assortment looks a bit weird but not totally discouraging.
The project file itself seems to be missing (or compiled into project.binary).
I am also a bit unsure why there's a (small) .pck file inside your project folder.
Anyway many of the scene files seem to be present so you might be able to just create a new project in a new folder and then copy all project files (in their original folder structure) in it.
You will have to add some adjustments like defining the startup scenes/singletons and doing the export setup but mayby all project files are there.
There's a decompiler here, but I don't know if it can decompile a binary project.godot file: