Connecting potentiometer with on/off switch to audio board
I can’t find enough information to talk about the wiring to the board, but I think I’ve figured out your pot.

It looks like a dual-gang pot (two potentiometers operated by the single shaft), typically used for stereo.

The front (nearest to the shaft) and middle plates are the two potentiometers. The middle pins should be the wipers.

The rear two pins are the (probably) push-on-push-off switch.

You should be able to verify all of this with an ohmmeter.