There are other examples, but I picture a Muslim who got caught and killed right after he just raped and cut off the girl's head. Now there is a guy that I personally believe to be in hell. Aside from possibly saying to myself - "May God have mercy on his soul," we should not pray for that guy.
Now if a devoted baptist preacher were to die during his sermon, we do not pray for him because we are certain he died outside of the Church. On that account and per the dogma, we know that man has no hope of salvation, which is the reason that we do not pray for him.
So this brings up the question what is fallible or infallible?
I think I now understand what some people I know are trying to say when they say we give to much power to what a Pope says.
The question we have to ask ourself first, is who does this serve? Who does it serve that you not pray for him?
It makes people pray less. It makes people lose charity. It makes. It makes people lean into rash judgments.
Does those results serve God or Satan?