Would you deny him the chance of salvation?
God won’t. No church would, and I don’t care if it is the pope himself hearing Castro’s repentance or the most humble Baptist preacher you can find.
He committed great sins. If he truly repents, he will eventually be with God, and that is a cause for celebration.
Of course, according to our theology, he is going to spend a LONG time in purgatory ....
Not if he were to gain a plenary indulgence.
http://www.catholic.org/clife/prayers/indulgc.php
God's Mercy is infinite. The value of Jesus’ act of redemption is infinite, and therefore, the treasury of the Church is infinite.