This can be stated in active form. Alternate translation: "that the man did not find proof that the girl was a virgin" (See: [[rc://en/ta/man/jit/figs-activepassive]])
The abstract nouns "proof" and "virginity" can be translated as verb phrases. Alternate translation: "something that proves that the girl has never had sexual relations" (See: [[rc://en/ta/man/jit/figs-abstractnouns]])