[Smush Pro] SmushPro Individual File Smush Failing

We have recently started experiencing a problem where we are unable to individually smush files. We get an error that says File Path Empty. However, bulk smush works fine. In addition, we have checked the folder where the files are stored and all expected thumbnails exist and are fully writeable. We are experiencing this on our staging and production environments and we have not made significant changes to either recently.