According to open theism, did God know that the crucifixion of Jesus would benefit anyone after him?

Ronald Nash challenges [open theism](https://en.wikipedia.org/wiki/Open_theism) in his book, *Life's Ultimate Questions*, in particular on the point of God's foreknowledge during the crucifixion of Jesus. Since God's knowledge of the future is "open" or "dynamic," according to open theism, he is not omniscient in the classical sense. Nash argues: > Think back to this God's conundrum at the time his Son was dying on the cross. At that moment, the finite God of open theism had no way of knowing if even one human being would accept his Son as Savior. This poor impotent deity faced the possibility that the suffering of his Son upon the cross would bring about the salvation of no one. (323) Nash seems to be ignoring the case of OT saints (whom presumably God knew would be saved through the death of Christ). But otherwise, is he right? Is he fairly representing the view of open theism? Do its adherents generally admit that God didn't know if Christ's death would result in a church, or indeed a single post-resurrection believer? If he didn't know, did he have any purpose for sending Jesus to earth other than saving OT saints? If there is disagreement on this among the various types of open theists, I'd like an overview of their positions.