Well, no. Omega-4 has a sister relay. A mass relay is incapable of functioning without one. Just because they don't specifically say "the Omega-4 relay has a sister relay" doesn't mean it doesn't have one. Everything in the game, in fact, does point to a sister relay near the Collector base. The game also never shows any of your squad mates eating. This is sort of like suggesting (or, more accurately, insisting) that because none of your squad-mates have a meal onscreen that they are absolutely, unquestionably, irrevocably vampires. Then going on to say that this means there is the plot hole of Vampires existing in the Mass Effect universe when nothing else has been supernatural in the game (well, except for telekinesis, mind-melding, giant, magical, mind-controlling sentient ships, and zombies). The way I see it, there are one of three possibilities: you aren't paying any attention, and then making stuff up, you have some kind of mental disorder, or you're manufacturing non-existent plot holes for the sole purpose of complaining about them on the internet. All of those are just kind of sad. In reference to the post before; we don't have any idea what the Reapers are actually capable of. We can guess, but that isn't the same thing as knowing. They're mile-long, sentient starships capable of doing things we can't imagine. I think it's pretty safe to say that if the Reapers built a base in the core, then they had a way of doing it, because they did it.
