Hey, finding those special chi- er, making those custom clothes is hard work.
A Much Too Silent Sea has been translated. When reading the in-game logs, I think it's implied that they had both Android higher ups and YoRHa on the Moon base, but now we know that just means 10H and her pod program. Now, all YoRHa are supposed to be in the dark about the fate of humanity except for the Commander, so 10H has been made to believe that she's in charge of a relay station for messages from the Counsel of Humanity and a backup base for humanity's data. Multiple times, she's figured out that there's no humans left from discovering that she's on the main base and knowing that the broadcasting room has no one inside. When she finds out, her pod always takes her down and deletes her memories of the truth.
You'd think Zinnia's superiors would man the base with personnel that would know the truth about humans, so they would be in on the deception... but when I think about the concert script, it seems like very few people actually know about the Moon Base's role in Project YoRHa. Zinnia wrote the original document detailing that he planned to use the Base to infer that Humans were still alive, but since the war had to end sometime, he knew he couldn't keep up the deception and decided to scrap it. However, his protege #9 seems to have gotten a hold of his plans, leaked it to some collaborators(?) and designed the logic virus backdoor to complete the illusion. So the actual amount of people who could man the base and still be in the know is very small. Looking at what happened to #9, they could all be dead.
And to anyone still left alive, I'd imagine that the prospect of a listless life on the moon tending to humanity's ghost is not too appetizing. So they'd rather kill this poor girl over and over than take up a boring, but necessary job. Well, the Android higher ups think that YoRHa androids aren't even "real" ones anyway. It's probably no skin off their noses.