The RowHeaderIndentation property is not applicable when the RowHeaderLayout property is set to 'Standard'
The RowHeaderIndentation property behaves differently based on the value of the RowHeaderLayout property.
When set to 'Compact', RowHeaderIndentation determines the offset between the left edge of a child header with respect to its immediate parent.
When set to 'SuperCompact', RowHeaderIndentation determines the offset between the header content (i.e., text, image, expansion indicator) and the left edge of the header.
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2