According to Encyclopedia Titanica, the name of the Assistant waiter you were looking for was Louis Corvella. You know that, in 1912, it was the early years of the Marconi system and some mistakes were done. That's why I do believe Orovello and Crovello was the same person.
Please, for instance, see the following article taken from ET archives. It's written "L. Crovetto, 17 [years old]".
Luigi Crovella was born on 19th September 1895 in the town of San Sebastiano del Po, in the province of Turin. He was the third son of Stefano Crovella and Cristina Ortalda. He emigrated to London where he succeed in becoming a waiter.