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]".
Friday 19 April 1912
London, 17 April, night
Italians aboard the Titanic numbered more than 50: two restaurant's directors L. Gatti, 36 years, and F. Scavino, two superintendents, Giuseppe Bochet, from savoy and Nannini: 17 waiters, 17 assistants some butlers, besides more than a dozen of waiters transferred from Olympic to Titanic at the last moment, and of those the names are unknown.
Here are the names of the waiters and of the assistants belonging to Titanic's crew:
Luigi Zarracchi, 26 years; F. Nannini 42; Montello; Pompeo Piazza 30; Roberto Urbino of 22; Ernesto valvassori 37; N. Bazzi 33; E. Ratti 23; C. Casali of 32; Gino Sesia of 34; G. Basilico 25; R. Vioni 32; V. Gilardini 31; V. Banfi 25; E. Poggi 26; E. De Napoli 24; L. Crovetto 17; Antonio Allaria 22; Battista Bernardi 22; Luigi Piatti of 17; Giovanni Saccaggi 24; Abele Rigozzi 22; G. De Martino 20; brothers A. and G. Peracchi, the first of 20 and the second of 18 years; G. Donati 19 years old; A. Pedrini 21; P. Rousseau, from savoy, of 49; G. Sachero 20; G. Monteverde 23; L. Desvernini 20; C. Levy 30; F. Bertoldi 24; F. Salussoli 25; E. Testoni 24; C. Sirtori, Angelo Rotta of 23; N. Bazzi, V. Pirotti, Giovanni Ferretti, Rinaldo Ricaldone of 24, G. De Marsico.
Italians colony in London is in consternation. Most of the shipwrecked were employed from year in the better hotels and restaurants of the city. Their family are afflicted, in anguish. A sad case is that one of the 22 years old waiter Urbino, that left unwillingly the very young wife that was pregnant and about to have the baby, last week.
The poor woman gave birth to a baby boy today. The relatives have charitably hid the terrible disaster from her.
Many of the waiters aboard the Titanic have wives and children in London, we hope that they were saved. The prominent men of the colony are thinking about a subscription for their families.
I have phoned to the White Star office in Southampton and learned that among the survivors picked by Carpathia there is the twenty years old waiter A. Peracchi [sic]. The fate of the others is unknown, but the fact that one is saved makes hope for the others.
We are waiting anxiously for new lists of the survivors. Among the crew there are no other italians. There is no italian name on the list, apart that one of a fireman John Podista, that from the news is an American citizen, but native of Italy.
Among the italian's passengers, in the last list sent from Carpathia there is only the name of Emilio Portalupi.[...]