If God knows the end before the beginning, he knows who is going to accept salvation through His Son Jesus before they are born. Is it fair to say that Jesus died on the cross, not for everybody, but only for those who He, the Father, and the Holy Spirit knew in advance?
God does know everyone who will ask for salvation. But John 1:29 and John 3:16 are two places that tell us Jesus died for the sins of the whole world. Matt. 7:7-8 and Romans 10:13 make it clear that anyone who asks for salvation will receive it. This would not be possible unless everyone’s sins are covered.
It is true that those who fail to ask for the pardon Jesus purchased for them will not benefit from what He did, but He did it for them just the same.