I’m a former Catholic, and I’m very knowledgeable on a number of Catholic miracles. There are only a few “good” one’s (Guadalupe, Fatima, Zeitoun, etc); the rest boil down to hearsay, exaggeration, wishful thinking and sometimes even outright lies. Yes, lies. There’s no stopping to what lengths some will go to convert others.
I can’t speak for other atheists, but no, it would not convince me. I know what I experienced that led me to the definitive conclusion that God doesn’t exist. By the way, this isn’t one of those Catholics who went to Mass only at Christmas and Easter. Quite to the contrary, this is a person who went to regular confession, Mass every week, frequent adoration, World Youth Day, prayed novenas, rosaries, read Scripture, read lives of the saints, and so forth. So nothing you reported could ever convince me, as I’m already convinced with what I discovered.
I speculate it won’t convince a large number of atheists. By definition, miracles are personal. If an atheist is going through a hard time, he/she isn’t going to be persuaded by a weird occurrence that happened in France hundreds of years ago.
I would say one benefit of being an atheist is that I can see Catholicism from the outset. To me, there’s nothing different between Catholicism and any other religion. They are all the same ultimately. Just look on these forums. Look at all the bickering. Does that seem godly to you? Can a kingdom divided upon itself, stand (cf. Mark 3:24)? That’s not something I want to be a part of. No, thank you.