I think if humans were ever going to meet intelligent extra-terrestrial life we would have been warned about it by God in revelation somewhere.
Intelligent, rational (therefore in some way ensouled) lifeforms, with a view of right and wrong, abstract thought etc, showing up on planet Earth and having no knowledge of a Triune God would shatter my faith. There would be too many "truths" that would have to be turned on their heads. Not unlike believing in Vatican II and the new springtime. You simply cannot square it with past belief and dogmatic teaching. People who believe that Vatican II is right, must believe that the Church before was wrong. Mutable truth is oxymoronic.
The idea that humans would have to convert a new planet of beings (and therefore, by inference, a whole universe of planets, like they did the American Indians would be a bridge too far. Especially, since NOTHING like this is mentioned in the Apocalypse or anywhere even semi-credible for that matter.
Then there is the issue of Our Lady. Not only is she Queen of the Angels but Queen of the Universe. If there are 1000s or millions of planets with intelligent ensouled life out there, and the universe is a huge place, so if there is one there are many, then giving one creature from one planet the honours that Our Lady is given seems strange. The Litany of the Blessed Virgin Mary would be a lie.
Our Lady cannot be "Queen of the Universe" just for the Solar System. That is silly as the Universe is not the Solar System. Nor can she be Queen of the Angels, because the Angels are not bound by the Solar System and would be the Angels of these other beings. Once God starts having multiple Our Lady like characters, the Holy Morf, The Wonderful Hermit of Zarg it all gets a bit silly.
Plus Matthew's descendent could never moderate the intergalactic forum wars that would go on and CathIntergalaticInfo.com So I'm agin' it.
Besides there is not one shred of evidence that ANY life even primordial slime, exists outside of the earth. And goodness knows scientists would give their vital organs to find it. Partly because they know it would underpin evolutionary theory and destroy what faith remains. Generally speaking I don't speculate in Flying Spaghetti monsters existing until some pasta or tomato sauce falls out of the sky and makes a case for it.