We damage the file so that no one can open it
If you do not have time to do some work by the deadline, then you can deliberately damage the file so that it does not open.
corrupt-a-file.net — free file destroyer. The service works with all formats, upload a working file to it and download the already damaged one.
The file will not be able to be opened or restored, so it will look like a technical problem and you will have time to finish the work.