He has. Purple wire between the neck and bridge volume pots, blue wire between bridge volume and tone and green wire between bridge and neck tone pots. You don't want a fourth ground wire between neck volume and neck tone to create a loop. It's not as the diagram, but they are all connected and its all good.

As long as the output ground is connected to one of those pots, then all should be fine. The solder joints, whilst not the neatest I've ever seen, all appear to have flowed across the surface of the pots and aren't blobby and suspect.

What I'm not 100% sure about are the three yellow wires soldered to the back of three separate pots as I can't see where they go.