The tone system consists of a capacitor and variable resistor connected in series between a signal input and ground. It doesn't matter if the capacitor is first or the variable resistor is first; it works just the same either way round. The variable resistor is the pot, with just two connections - between the end of the track and the wiper connection. You can swap the two pot connections over, so it doesn't matter if the signal is connected to the end and the cap to the wiper, or the cap is connected to the track end and the signal to the wiper.

On the Northwest Guitars diagram, note that the wire leg of the capacitor is connected to the end of the track on the volume pot - but it is also used to connect that track end to the back of the volume pot - which is also connected to ground. So it is electrically equivalent to the PBG way of wiring.

You obviously don't have the ground connection from the jack socket to the back of a pot yet, or the output signal connection, or the pickup connections.

But what you really do need for best long-term operation is a ground wire link between the backs of the two pots. Because the Tele control plate is metal, you can get away with not having that wire as the plate itself will connect the two pots (as long as at least the back of one of them is grounded). But pots become lose over time, and they may become loose enough so that the connection between the pots is either lost or becomes a very high resistance, at which point the tone control (or volume control depending on which pot has the direct connection to ground) starts to play up, or you end up with a much noisier guitar. This is easily fixed by tightening up the nuts again - but it's not not something you want to happen mid-gig. So simply linking the back of the pots with a bit of wire prevents that happening.

The Northwest Guitar diagram method would mitigate against that to a large extent if the jack ground wire went to the back of the volume pot, as the cap would then be directly wired to a good ground, even if the volume pot nut came loose, so the tone and volume circuits would always work as designed (you'd just lose the shielding of the pot that the case normally provides). But it is best to have that soldered connection between the back of the pots for long-term piece of mind.