The Grid in a GridListControl is a virtual grid. To set any of the styles, you will need to handle the PrepareViewStyleInfo event and set the style there.
grdLst.Grid.PrepareViewStyleInfo += new GridPrepareViewStyleInfoEventHandler(PVSI);
//....
private void PVSI(object sender, GridPrepareViewStyleInfoEventArgs e)
{
if( e.ColIndex == 2 && e.RowIndex > 0)
e.Style.Format = "C";
}