Если верить Цицерону. то ни один из них не мог быть ни комендантом Карр (хотя это и вероятно. если речь шла не о легатской должности, а о военном трибунате), ни претором-49 (100%-но). Цицерон весной 56 г. называет обоих aduluscens, то есть к этому моменту они не занимали никакой должности. Вряд ли "юноша" 56 г. мог быть легатом 53 г. (хотя военным трибуном мог) и наверняка он не был претором 49 года.
У Броугтона, кстати, Г.Копоний - префект Карр и претор-49.
Со значением слова adulescens не все так просто.
Словарь Льюиса и Шорта
B. Subst. comm. gen., one who has not yet attained maturity, a youth, a young man; a young woman, a maiden (between the puer and juvenis, from the 15th or 17th until past the 30th year,
often even until near the 40th; but the same person is often called in one place adulescens, and in another juvenis, e. g. Cic. Fam. 2, 1, with Att. 2, 12; cf. id. Top. 7;
often the adulescentia passes beyond the period of manhood, even to senectus; while in other cases adulescentia is limited to 25 years, Cic. Tusc. 2, 1, 2 Goer.: “Primo gradu usque ad annum XV. pueros dictos, quod sint puri, i. e. impubes. Secundo ad XXX. annum ab adolescendo sic nominatos,” Varr. ap. Censor. cap. 14. “Tertia (aetas) adulescentia ad gignendum adulta, quae porrigitur (ab anno XIV.) usque ad vigesimum octavum annum,” Isid. Orig. 11, 2, 4.
Thus Cicero, in de Or. 2, 2, calls Crassus adulescens, though he was 34 years old; in id. Phil. 2, 44, Brutus and Cassius, when in their 40th year, are called adulescentes; and in id. ib. 46, Cicero calls himself, at the time of his consulship, i. e. in his 44th year, adulescens; cf. Manut. ap. Cic. Fam. 2, 1, p. 146): tute me ut fateare faciam esse adulescentem moribus, Plaut. Mil. 3, 1, 67 : bonus adulescens, Ter. And. 4, 7, 4 : adulescentes bonā indole praediti, Cic. Sen. 8, 26 : adulescens luxu perditus, Ter. Ad. 4, 7, 42 : adulescens perditus et dissolutus, Cic. Tusc. 4, 25 ; Vulg. Gen. 34, 19; ib. Matt. 19, 20.--Homo and adulescens are often used together: amanti homini adulescenti, Plaut. Trin. 4, 2, 94 ; Ter. Phorm. 5, 9, 53; Cic. Fam. 2, 15: hoc se labore durant homines adulescentes, Caes. B. G. 6, 28 ; Sall. C. 38; id. J. 6; Liv. 2, 6.-- Fem.: optimae adulescenti facere injuriam, Ter. And. 3, 2, 8 : Africani filia adulescens, Cic. Div. 1, 18 fin. The young Romans who attended the proconsuls and propraetors in the provinces were sometimes called adulescentes (commonly contubernales), Caes. B. C. 1, 23; 1, 51. Sometimes adulescens serves to distinguish the younger of two persons of the same name: Brutus adulescens, Caes. B. G. 7, 87 : P. Crassus adulescens, id. ib. 1, 52, and 3, 7: L. Caesar adulescens, id. B. C. 1, 8 .
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