DataLabels are a collection of labels that display text defined at each point along the X or Y-axes. DataLabels annotation cannot be used for the Z-axis.
Use the RowLabels and ColumnLabels ChartGroups properties to define and edit DataLabels. These properties can be accessed through the Chart3DDataLabel Collection Editor. The respective editors for RowLabels and ColumnLabels can be accessed by:
Set AnnoMethod to DataLabels for an axis and use this tab to define the labels.