Have a Skoda Octavia 2014 2.0L TDI elegance estate
Seems to be a similar / the same coolant overheating issue. First occurred at 39,800 miles in Feb 2020 when getting up to speed on the motorway shortly after start of the journey. Temperature gauge increases rapidly, until the red zone and the Engine overheat warning turns on. Then need to switch off or slow down for it to return to normal 90 deg temp.
I find that if you drive more slowly (50mph or below) for 20 mins or so, the temperature doesn't reach the red zone, and then the problem then seems to go away - the pump/impeller frees itself? Similarly if after a long journey at speed you start the car again soon, while still warm, the problem doesn't occur. Seems that our pump is sticking but can free itself, once all warmed up, if that's the problem.
Tried Marshall Skoda Croydon - no interest in contribution. Car well outside warranty and not serviced at Skoda dealer since 2017. Quoted to fix cambelt and water pump for £590. Appeared not to have heard of this problem.
Went to very local garage, but looked at diagnostics and nothing there. Unwilling to do work where the problem was not showing up.
Volks in Sutton will do the water pump and cambelt for £419.