[6apcyk]

Всё вроде получилось

void insertClearCol(int _col, int _workSheet = 1, int _offset = 0)
{
COM comCols,
comWorkSheet,
comCol, comColTarget, comRange;
COMVariant comColVariant;
;

if (! m_comDocument)
throw error(strFmt("@DIS6401", this.getApplicationName()));
comWorkSheet = this.getWorkSheet(_workSheet);
comCols = comWorkSheet.columns();
comColVariant = comCols.item(_col);
comCol = COM::createFromVariant(comColVariant);
comCol.insert();
}