I do not have an Arduino UNO but an Arduino DUE. I suppose pins 8 to 11 are compatible with the same pins in Arduino UNO. The same for pin 2, 3 and 4. So I did not change anything in your sketch. I connected everything as in video, but the the leds in motor drive are off and motor does not react to encoder. I checked the motor, drive and encoder. They are OK.
Do you have any idea, what is going wrong?