“Sounds like he could use our prayers.”
Could have.
He’s dead now.
He had plenty of chances and I’m sure plenty of people praying for him.
Prayers can certainly be offered after the fact. We are linear, and constrained by time. God is above time. He created it for us, but it doesn’t limit Him. He knows the end from the beginning.
For example, if we pray for this atheist now, God will have known, while the man was still alive, that such prayers would be offered. God heard them before we uttered them [provided we in fact pray]. Any help a believer’s prayer might be for this atheist in his last earthly moments can still be afforded. It only requires us to recognize that God’s omniscience and omnipresence prevent linear time from constraining Him in any way.