Has this happened again? The idea that you held the pedal to the floor leads me to think it was flooded. By depressing the pedal, you turn off the injectors to clear a flooded engine. If it was flooded, it would likely run exactly how you described.
Let me know if it has happened again and if you were able to retrieve any diagnostic trouble codes. Because of the model year, you should scan the entire can-bus to see if there are codes. CAN stands for controller area network. Basically, all computers/modules are tied together via a few wires. This type of scan will retrieve codes regardless of the module storing them. Here is a quick video showing it being done:
Let me know. Also, the Polo isn't offered in the US, so my technical information is very limited, but I will do what I can to help.
Take care and Happy New Year,
Thursday, December 30th, 2021 AT 10:00 PM