New vaults won't operate in base preview version, and hasn't functioned correctly since update release 1.21.0.20. Ominous vaults function correctly since first released in 1.21.0.20, however, if regular non ominous vault is selected from creative inventory, and trial key is used on it it successfully drops loot. To clerify, the vaults that naturally spawn in trial chambers do not drop loot when trial key is used; the sound the vault makes when a player has a key in their inventory still is produced, but unable to use said key. The ominous vault function as designed, no issues, and will drop loot when ominous key is used. Finally, before 1.21.0.20 was rolled out, the non ominous vault functioned as originally designed. Thank you for reading this.