Rather fly with an airline that has direct UK/SA flights

My partner flew Swiss Air London Heathrow to Johannesburg OR Tambo, after booking on the Lufthansa website. She did not realise that it wasn't Lufthansa flights, but that's irrelevant.

Her flight from LHR into Zurich missed the connecting ORT flight. Passengers were as expected accommodated in a hotel, with breakfast included. But her claim for the taxi fare of €73 back to the airport has been denied, citing "air traffic flow management issues". There was no alternative or supp**** transport from hotel to airport and the Swiss desk instructed her to lodge a claim. Which has been done on the Swiss Air website. Really?!