Sorry, I’ve been away at a new job and haven’t been looking in.
You can download the entire zip from here: https://github.com/EpicGames/UnrealEngine
Once you have requested access to that page from here: https:///ue4-on-github
It’ll take a day or two depending on when you request it, but then you can go to the github link and just download the zip and find the ArtToolsOSX folder. Or just download the Dropbox link 