Hmm, well, it would seem to me we have, from left to right, a group of 4 vertical daughter boards for one channel (boards 1, 2, 3 and 4), then another group of 4 vertical daughter boards for the other channel (boards 5, 6, 7 and 8), then a group of 3 horizontal daughter boards with the output relays on (these are not very interesting so I will not mention them again). The boards in position 1 and 5 look similar, boards 2 and 6 look similar, boards 3 and 7 look similar, and boards 4 and 8 look similar. Hard to say why the pots are not symetrical with the cards, but again I would assume left to right that pots 1, 2 and 3 are for one channel, 4, 5 and 6 are the other channel. Logically boards 2 and 3, and boards 6 and 7 are the mid frequency filters, the bits missing in my NAXO 2-4 PCB photo I linked to earlier. So the question is whether cards 1 and 5 are low frequencies and 4 and 8 high frequencies, or vice versa.
Rather than disturb the boards to trace the tracks, how about you don't
if you did want to you could just pull board 1 and show both sides and I could (probably!) match it to one of the NAXO sections in the schematic. Alternatively:
Kit Ryan gives a great run down on setting up a NAXO 3-6
here which you could follow, mark with a pencil the orientation as the pots are, then with the system playing use a nice plastic pot twiddler to get in there and and give it a go. Pot 1 will turn up/down the low/high frequencies on channel 1/2, have a listen, you will work it out! Once you know what pot 1 does you should be away. My total guess is the pots go:
Pot 1 Low Channel 1
Pot 2 Mid Channel 1
Pot 3 High Channel 1
Pot 4 Low Channel 2
Pot 5 Mid Channel 2
Pot 6 High Channel 2
I hope that helps, apologies if the suck it and see approach is teaching Grandma to suck eggs.