Well, I would think that the dark system’s name (if they even exist) on the nav panel would be something obviously odd, something so different as to grab attention, maybe “UNKOWN SYSTEM” for example.
From a Stellar Cartography point of view, the system names on our galaxy map are assigned by humans, the names represent systems in the ships database given to stars which can be observed because they are points of light in the sky or because they have great mass which can be measured from far away. A dark system wouldn’t have any such name assigned to it because without the light nor large mass of a main star, Stellar Cartography wouldn’t even know it existed. The ship’s sensors detect systems around us in flight and then names them on the nav panel via pulling names from the database based on our position. Now, if the ship were to detect something for which it had no name for it’s positional data, how would it label such a system? I’d like to think the name would stand out as something very different than the mapped stars around it. If it’s just a normal system name then we’ll never find any possible dark systems, LOL.
Heck, for that matter dark systems might even actually SHOW on the gal map, but without a visible star there you’d probably hardly ever notice it unless you moused directly over it, or unless you plotted a route that just happened to use it. As if our gal maps just always had the filter for “dark systems” turned off without any way to turn it on, heh.
Of course, they might not exist at all either…..