I've been staring at the first ancient ruins map for the past couple hours and I think I have something.
The first thought is that the ruins themselves are perhaps intended to be a failsafe map of the network. The obelisks would tell you everything if they were functional.
But if they fail, they probably fail due to passage of time, a long one. In that time stars would probably shift so you can't just point to the direction of the next site. Instead you have to describe the star system.
Now humans would describe the star system, because Earth is a planet. However, guardians may originate from a moon of a gas giant and as a result they may consider gas giants much more important. So perhaps they would not describe the star system, but just the gas giant and it's moons.
Please, rate my craziness:
http://i.imgur.com/zbY4bil.png
Only one binary gas giant matches the interpretation, SYNUEFE ZL-J D10-119 12 & 13, and therefore I divine that the ancient ruins are located on SYNUEFE ZL-J D10-119 12 A. The moon is indeed landable.
Now either someone show me where I made a mistake or someone who has a bit of understanding of astronomy figure out which part of that moon would always see the first ancient ruins. I don't believe in -31, -128 nor in combing the entire moon