"Salvation is of Israel" All the saints, the biblicas sense not the RC sense, would be the rest of Israel's offspring.
Caiaphas was one of Israel's offspring. Do you include him?
Judas Iscariot was one of Israel's offspring. Do you include him?
John 1:13 says that God's children are not born that way of natural descent. Sounds like you think they are. Shall I trust you, or the Word alone?