What is the secret behind the difference in the use of the preposition "عليه" (upon it) in Surah Hud, verse 12, and "إليه" (to it) in Surah Al-Furqan, verse 8, when referring to the descent of treasure?

Both verbs, "anzala" (to send down) and "alqaa" (to cast/throw), can be transitive with either "ila" (to) or "ala" (upon), and both are correct. This is a testament to the richness and breadth of the Arabic language.