Can you verify that when the theme was zipped it did not contain “__MACOSX” or “.DS_Store”, this is placed in zip files when compressed on a MAC.
I used a Windows VM, downloaded the file from themeforest, then uploaded to my ubuntu AWS instance, unzipped the theme and I still get “__MACOSX” or “.DS_Store” files.
If I do the commands below it removes them, but totally breaks the theme.
find . -name “__MACOSX” -exec rm -rv {} \;
find . -name “.DS_Store” -exec rm -v {} \;