We are aware of the issue with the badge emails resending to everyone, we apologise for the inconvenience - learn more here.
See https://www.dropboxforum.com/t5/Files-folders/Filenames-become-lowercase-when-attaching-from-DropBox-to-Mail/td-p/349737. Filenames should not become all lowercase when exporting a file from Drop...
Why won't Dropbox fix this bug. Even if zero community members ask for it, an obvious and irritating bug should be fixed.