1: Measure voltage at the top of the pot with the PNP switched on and off. Observe if the PNP high-side switch works as intended.
2: Take a regular pot (a manual one), tie one end to 3.3V, the other to GND and the wiper to an input on the ADS1115. Write a small sketch that prints out the reading of that ADS channel. Observe if the measured value behaves as anticipated when you move the wiper position (aka turn the pot).
Then combine 1 & 2.