Soverick was not targeted specifically for the position. The fact that he became the child of the plane was not personal or orchestrated.
The net was cast and whoever was too big for the net would have been captured. Or in this case, whoever was too big for the net would have become the child of the plane. So Soverick has only himself to blame. He was too powerful and talented for his level. He stood out amongst his peers and was captured for it.
It was also his existence that triggered the war against the gods which allowed the creation of the divine dungeon. The child of sages simply choreographed the war in his favor to get a slot in the realm lord's project.
The child of the sages had to go to all these lengths for the opportunity because the realm was not offering it to Origin gods even if they have supreme laws and are about to become world gods. The realm lord only offered the opportunity to world gods.