How Do I Check the Dates Actually Worked?
Open a few photos and look at the date inside them, not at the file date in the folder.
Pick a handful from different years. On Windows, right-click, Properties, Details, and read Date Taken. On a Mac, open in Preview and press Command-I. That is the value everything else follows.
Do not judge by the folder listing. It shows file dates by default, which will be today because the files were just written.
Takeout JSON Metadata Fixer also gives you counts at the end: how many were organized, how many were located, and how many it could not place. It runs on your own computer and is free for your first 500 photos.