It is the same thing for you Steven. Your zip file contains a folder and in the folder you have the actual module files.
When we unzip the module we end up with
And because of that the extension is telling you that you are missing an index.html file, but in fact the file is there.
Don't worry about that -> when you install your module the index.html files should be there.
Index.html says it missing
5 years 1 week ago #18087