A king does not have to want Egypt to end up there; he only has to leave the road legal.
Sealed routes get unsealed by reasonable arguments. Nobody proposes a return to bondage; they propose an acquisition, a strategic advantage, and the old road becomes a supply line before anyone admits what it is.
Yahweh binds the throne by statute rather than by conviction, because a rule written in a strong hour governs the self that shows up tired and frightened. A decision left to the judgment of the moment gets renegotiated by the moment, and the moment always has a case for horses. What a nation pays for leaving the route legal is the direction it already bled to gain.