Confused about setting up column sorting in DataTable

I setup a backend API page load then configured the DataTable's "Generating Children from Variable" as show:


The data is returned fine into the DataTable (but, annoying, I can only see to show a maximum of 10 rows at a time).

I then attempted to setup column sorting, and on the first DataTableHeader, I configured:


I then created an action on the DataTable to detect the "On Page Sort" change, and configured it as follows:

The action is getting invoked (I followed that action with an alert, which shows the index column I clicked on), but the DataTable never refreshes with the sort. Nothing happens. Any ideas would be greatly appreciated.

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