Why did Solomon not get the Ark back from Ethiopia?

In the Kebra Nagast Solomon does try. As soon as Zadok finds wooden boards in place of Zion, the king sends out horsemen and rides after his son with an army, meaning to bring back Zion and kill the men who took her. He cannot catch them. People in Egypt and Gaza tell him the travellers passed days earlier in wagons that moved above the ground, faster than eagles, and an envoy of Pharaoh reports that the idols of Egypt fell before them. Solomon turns back and weeps in his tent. The Spirit of Prophecy then tells him this happened by the will of God, and that Zion has not gone to a stranger but to his own firstborn, who will sit on David's throne. The elders of Jerusalem add that Zion has never been moved unless she and God wished it, as the Philistines once learned. Solomon accepts this, has the boards gilded to look like Zion, and binds the elders to keep the loss secret.