Zamiast tego używaj tego;
set player's current inventory's slot [slot] to ..
Nie polecam tego rozwiązania..
Co do problemu..
on inventory click:
if name of player's current inventory is "&6&lVip":
cancel event
if clicked slot is 10:
open chest with 3 rows named "sss" to player
set player's current inventory's slot 0 to diamond