The PivotGrid is designed to display aggregated and grouped values of the underlying data not the data itself. So you won't be able to see any particular values from the data source in the PivotGrid as the cells are associated with a aggregated values of few items from the ItemsSource.
You might want to check the GridView
control which also supports grouping and filtering and each cell there is associated with a particular property of particular item from the ItemsSource.
Hope this helps.
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