Lex did not need to explain who Barley was since finding him was one of the recent popular requests for oracles in the Origin realm, right behind finding Lex. While initially finding Barley was easy, it had been a while since he disappeared from both public view as well as from the effects of divination.
But unless he was using an abnormally powerful protection measure, such as the formation within the Inn, there would always be ways to find him. For example, most means of protection from divination only target the more common or mainstream methods.
More unique methods, such as Vera's, can often circumvent such protection measures. For example, as long as Barley met Vera in person at some point in her life, she could divine her own future and find him, or predict where and when he could be found at that time. After all, the target of her divination is herself, not him.