For the dependency, you need to use the addon's folder name. For example, an addon that appears in-game as "My Addon: Awesome Plugin!" probably has a folder name of "MyAddon_AwesomePlugin". I have no idea what Stuf's folder is named, but it's in your addons folder, so you can figure it out easily.
The global would be whatever is at the root of your "stuf.units.party" path -- if that's the actual path you're using successfully in your script, then the global would be "stuf". Given your comment about capitalization, though, maybe it's "Stuf" or "STUF" instead. Don't use quotes around it in your code, though.