Again, not responsive to the question: if he is already saved will becoming a believing Catholic have any effect on salvation?
We don't preach the Gospel to change the outcome. We preach the Gospel to facilitate God's outcome. Get the difference?
Sure, you want it both ways. God does everything, man's actions matter. Sorry, if double predestination is true, everyone is saved or doomed - no matter what you do.
And if you continually refuse to answer the simple question I've asked
I have absolutely no problem answering it, except that it's irrelevant. God is omniscient and omnipotent and he created man with free will.
The hateful unjust god of Calvin still does not necessarily follow - and if it does follow, we warp god into something quite un-Godly.
lol. Non-responsive? Perhaps the problem is that it is not the answer you're hoping for. The answer assumes a fallacy at the outset. Someone who is "saved" is most likely not a Roman Catholic. Not for long. And someone who is saved most likely would never regress by becoming a Roman Catholic.
Hope that's clear enough for you.
I have absolutely no problem answering it, except that it's irrelevant.
Humor me. You may want to think it's "irrelevant," but it's far more interesting that you seem unable or unwilling to give it a shot.
Did God know everything that would ever occur in time at the moment of creation?