Thanks there! There's MacOS resource content in the Zip archive. Aside from the 'untidiness', it could potentially leak identifying information. Back when I owned an iBook, I used the "ditto --norsrc srcDir destDir" command, but it's also doable with "zip -d filename.zip __MACOSX/\*", or with Keka and setting an option in it.

Thank you for your comment. I am unable to locate this data despite doing the basic "show hidden files/folders" Could help me out? I am happy to use any messaging app you may desire if it's easier for you. Thanks in advanced!