Remember that ancient texts were often not written about until up to 1,000 years later. For example the J source in Genesis-2 Kings was written not until after 922 BCE .
Once again, you’re taking a position that is directly contrary to the opinion of Jesus and the rest of the bible:
John 5:46 “If you believed Moses, you would believe me, for he wrote about me.”
Exodus 24:4 Moses then wrote down everything the LORD had said.
Exodus 34:27 Then the LORD said to Moses, "Write down these words, for in accordance with these words I have made a covenant with you and with Israel."
Deut 27:8 “And you shall write very clearly all the words of this law on these stones you have set up."