How to fix Mach-O file unable to be generated?

After more messing around, I discovered it’s something to do with the pasting of the file directly into the project, potentially even due to moving them into folders right after loading from the cloud. I fixed this error by creating a new file, going to the original project, copying the contents of a file and then going back to playgrounds on the file I had just created and pasting in the entire contents. I did this for all project files. After fixing the errors as they arose per file (simply missing classes of files not yet pasted in) the app worked fine!