Whether the Railway Safety Regulator has completed an investigation into (a) the incident where an empty Transnet Freight Rail Blue train derailed at the Union Station Loop in Germiston on Sunday, 7 November 2021 and (b) two Blue train coaches derailing within the Salvokop Blue Train train-yard in January 2022; if not, what are the reasons that no investigation has taken place; if so, will he furnish Mr T B Mabhena with a copy of the report?