It looks close to correct.
The issue might be that the directory is 'Media' instead of 'media'. Case counts in Android. That is something you will want to be careful of in your file names as well. They need to be spelled the same in your code and the file (case sensitivity) and there must be no spaces in the names.
The problem is that it is tricky to get Windows to let you rename a directory and only change the case.
In WinZip, create a new zip file, but hit cancel when it asks about what to add. Then click on 'Actions' in the menu bar and select 'New Folder'. Name it (exactly) 'media'. Then select it and, from File Manager, drag all the contents of your Media directory into WinZip. Click on the 'Add' button to accept them. And then try submitting that zip file (after closing WinZip, of course).
Cheers,
Ancient Lady
AGK Community Tester and AppGameKit Master