Yes you plugged in correctly. Pin 1 on motherboard with corner market cable Red(5v) - + Gnd. Exactly like the yellow USB connector. But should push the black connector all the way into the board and not exposed pins like in your picture. Look at how yellow connector is plugged all the way in.

Usually if i encounter connectivity problems, a spray on the connectors from a can of contact cleaner is very helpful. It helps to remove some corrosion/dust/ oil coating on the exposed connector pins.

Have you checked for swollen capacitors on the motherboard? Refer to this thread: https://forum.lowyat.net/topic/341368