Just read your contribution to the Spreadsheet Workbench page. 2 things caught my attention:
1. FreeCAD does allow duplicate labels in the same document. There is a related setting: Edit > Preferences... > General > Document > Allow duplicate object labels in one document. But if there are spreadsheets with duplicate labels then they cannot be referenced by their label.
2. The internal name of objects is readily available in the GUI. If you select an object in the Tree it is displayed in the status bar. So what you are saying in this regard ('The internal name of the spreadsheet is not readily available anywhere except within the expression editor') is not correct.