I think you can handle this by not adding those columns to Excel at all. You can try to do this by using code like this every time you loop through the columns.
int offset = 0;
if (j == 2 || j == 3 || j == 4) {
sheet.Range[1,j+1].ColumnWidth = 0;
} else {
if (grid.TableModel.ColWidths[j] == 0){
offset = 3;
} else {
sheet.Range[1,j+1-offset].ColumnWidth = (grid.TableModel.ColWidths[j]/7.43);
}
}
You would need to do something similar in every loop through the columns, skipping 2,3,4 and offsetting the column indexes in the excel sheet by 3 as needed.
