You might want to find another shop.

That code refers to a faulty sensor or a problem with its wiring/connector.

The output speed sensor detects the revolution of the idler gear parking pawl lock gear and emits a pulse signal. The pulse signal is sent to the Transmission Control Module (TCM) which converts it into vehicle speed.

The thing to do with that P0722 code is to check the pulse signal (waveforms) of the Input & Output speed sensors.

The reason for the extra effort, on your Sorento they have to remove the valve body to replace the input and output speed sensors.

(they don't have to remove/replace the transmission)

So it should look like these at specific input/output rpms

Pretty easy to determine if the sensor/wiring has failed. The output speed sensor voltage waveform would be flatlined or dropping in and out.