He told me the model did not update, so I checked it out.
When the source workbook and the destination workbook are open on the same computer, links are updated automatically.
Note: Tableau does not provide support for programs that customers create that use the Tableau REST API.
For help with your code, submit questions and ask for help on the Tableau developer community forums.
Anyway, I put together a pretty simple spreadsheet where a single cell will reference one other file, very simple.
So I closed out of my work so my boss could review.