So, where do the wishes come from? The Harvester disables her shipboard navigation systems every time she begins the trip. So, in the strictest sense, even she does not know. But she can find her way. At the bluish star, she taps the thrusters twice. When there's the triangle of pinkish stars, she hangs a hard right. Then, right at the edge of the dust cloud, where the icy specks merely tickle the hull of her ship, the Harvester turns the hyper engines on full. She doesn't watch the ship clock or count the seconds. When enough time has passed, the Harvester just knows, and she brings the ship to a full stop.
Outside, the space is clear. Her path brings the Harvester to the nadir of an orbit perpendicular to the plane of asteroids orbiting her own, secret, deathly silent black hole. An extra second on the hyper drive and her ship would be too close, but the Harvester never gets it wrong.
From her vantage point, the Harvester scans the rings of asteroids, but she almost always finds what she's looking for by the naked eye. So, with her graying tresses mirrored, shadowy in the glass, the Harvester looks past her reflection and watches the asteroids through the ship windows. Together they circle the black hole, swirling toward it, until they disappear. Except for one. She'll spot one, and, then, after watching long enough, she'll spot another.
Individual asteroids following their own, bizarre gravitational rules. Ignoring the pull of the black hole.
The Harvester notes these aberrations down, and when she's found enough of them... She harvests. Inside each aberrant asteroid, sometimes a canker on its surface and sometimes a heart in its very core, a geode of hypercrystals resides. The Harvester chips them off or cracks the asteroid wide, freeing the hidden crystals.
The crystals, when she finds them, are coupled to complimentary geodes in complimentary asteroids orbiting entirely different gravitational wells in entirely different, alternate universes. The asteroids, while reigned by their geodes, follow these alternate gravity paths, creating their telltale, seemingly illogical orbits. Why so many there? Mixed into the field of asteroids around that black hole? The Harvester doesn't know, but a hyperstar exploded there. Back when the black hole began.