Does Paul trace the one who came out of Israel back further than the patriarchs?
Yes. Paul traces the One who came out of Israel further back than the patriarchs, all the way to Genesis 3:15. Immediately after Adam and Eve fell, God promised a Redeemer, showing that the redemptive promise predates the covenants given to the patriarchs.
Les explains that the One Paul refers to came out of all the things Israel had enjoyed, namely the covenants given to the patriarchs, but the connection goes much further back. Les goes to Genesis chapter 3, where Adam and Eve had just eaten the forbidden fruit and fallen. God knew they would sin, and immediately after the fall He promised a Redeemer in Genesis 3:15. This fits the Christ of redemption, who redeems fallen creation, as Les earlier taught from Romans chapter 8.
Who are Israelites; to whom pertaineth the adoption, and the glory, and the covenants, and the giving of the law, and the service of God, and the promises;