Lol, you need to take a deep breath and not take this game so seriously. I don't need to show any "proof" of anything, I'm not the one making outlandish claims about how we could magically map the exact location and stellar content of every single one of the 400 billion systems in the galaxy to 100% accuracy.
So we've got thousands of these probes that we're sending out at FTL speeds to map the entire galaxy perfectly (in record time too apparently), and they have sensors to detect the stars and triangulate their positions to pinpoint accuracy, and they're going to be smart enough to visit or catalogue every single system in their range... but they're going to report nothing about the planets and moons in the systems? They don't need FSS or anything like that, basic sensors would work fine. Oh and also they're going magically see all the brown dwarfs that are too dim to see beyond a couple of lightyears from their tiny shipboard telescopes too.
Outlandish claims you say? Well then, explain how we got the map in the first place? Maybe Thargoids gave it to us? Or Guardians? Yeah, roight... It was the probes, millions of them.... And yes, their probes with their tiny telescopes were able to spot the brown dwarf by using GRASPADIS array (gravitational space distortion sensors)... Swarm of probes is linked and creates an array that measures spacetime distortions to detect objects that are not visible to any other sensors.... This is also how we are detecting small black holes... But let me guess, you will also deny this, roight?