PrepareViewStyleInfo is mainly used for setting drawing properties (like BackColor). To set behavioral properties like Clickable, try using teh grid.Model.QueryCellInfo event.
//in formload
this.gridDataBoundGrid1.Model.QueryCellInfo += new GridQueryCellInfoEventHandler(Model_QueryCellInfo);
//the handler
private void Model_QueryCellInfo(object sender, GridQueryCellInfoEventArgs e)
{
if(e.ColIndex == 2 && e.RowIndex == 2)
e.Style.Clickable = false;
}