What is the purpose of the expression box? I only ask, becuse I don't know why people use them, or rather, I don't know what makes them think to use them in situations where they don't seem to make sense to me ("to me" being the key, so don't worry).
Just drag the group from your SharePoint list connection onto the canvas and let it create a repeating table automatically. This will repeat all the data in the list, and you can set it to only show the @Name column. Easy as Pie.