Both of Pliny the Younger and Josephus were born decades after Christ was supposedly killed, and their writings on the topic date from the very late 1st century to early 2nd century.
They were not contemporary.
Also, the biblical texts are not reliable, as we don't know who wrote them, and are not backed by any other piece of evidence. We can't even prove Jesus existed, much less fulfilled prophecies as there is no contemporary evidence for him at all.
All we have to go on is writings from historians that lived and worked in an era where the eyewitnesses would have been long dead (that goes for the Gospels too). All people like Josephus were able to report is the beliefs of early Christians, and no historical account of Jesus himself.
Since when has being a contemporary of a person become an absolute necessity in compiling an accurate historical account of said person?
We do know who wrote the biblical texts. This is not even an issue of contention in contemporary biblical scholarship. We have Christian and non-Christian evidence for the reliability of the New Testament as indicated by notable scholars such as Dr. R.T. France when he says: "Non-Christian evidence substantiates the fact of Jesus' existence, and His popular following, His execution and the rough date" (France, NBD, 564)
Edwin Yamauchi, professor of history at Miami University, asserts that we have more and better historical documentation for Jesus than for any other religious founder (e.g., Zoroaster, Buddha, or Muhammad). Of the non-biblical sources testifying of Christ, Yamauchi concludes:
1. Jesus was a Jewish teacher
2. Many people believed that He performed healings and exorcisms
3. He was rejected by the Jewish leaders
4. He was crucified under Pontius Pilate in the reign of Tiberius
5. Despite His shameful death, His followers, who believed that He was still alive, spread beyond Palestine so that there were multitudes of them in Rome by A.D. 64.
6. All kinds of people from the cities and countryside-men and women, slave and free-worshipped Him as God by the beginning of the second century. (Yamauchi, JUF, 221,222).
Jesus was a real man and the fact that I have to even discuss this with you is quite incredible.