What the spreadsheet contains
Each row holds the file name, camera, lens, aperture, shutter speed, ISO, focal length, exposure bias, flash, date taken, width and height, latitude, longitude and altitude, and the software that last saved the file. A photo without EXIF still gets a row with its name and size, which is useful in itself: screenshots and images saved from websites or messaging apps usually carry nothing.
The report reads the original files. The second branch also starts from the originals, so the clean copies are made independently and the report still shows what the originals contained.