Well, if you need the path to the parent folder to set as root of copy:
dim parentFolderPath
parentFolderPath = WScript.CreateObject("Scripting.FileSystemObject").GetFolder(objFolder.self.Path).ParentFolder.Path
EDIT
You need the name of the selected source directory added to the path of the selected destination so
Set fso = WScript.CreateObject("Scripting.FileSystemObject")
sSourceFolderName = fso.GetFolder(objFolder.self.Path).Name
sDestination = Chr(34) & objDest.self.Path & "\" & sSourceFolderName & Chr(34)
Robocopy will handle the target directory creation