That's a pretty awful thing to wish on someone.
The Gospel is open and available to the worst mass murderer in the world to a child old enough to understand. If one repents and believes Jesus, one can enter Heaven. This can happen at any point in their life. From very early to very late.
Remember...Paul was a persecutor of Christians.
Moses was a murderer.
David was an adultery and arranged for a murder.
Some of the "biggest" names in the OT have a pretty bad rap sheet. Yet, they are recorded in Hebrews as having faith.
This is the wonder of the unmerited favor of God and the reflection of His love and His justice coming together at the cross.
Unfortunately, many hear the message and turn away, thinking they are better than the mass murderer, so surely they will go to heaven. They will not.