There is a book out I recommend on this topic by Dr. Paul Thigpen, called "Extraterrestrial Intelligence and the Catholic Faith: Are We Alone in the Universe with God and the Angels?"
In short, though, Christ's sacrifice to redeem humanity does not preclude, or prevent other plans for other species.
Some say the government is keeping aliens evidence from the world because it would shatter people's religious faith. If that is true, they are very, very wrong. Thigpen is convinced aliens have visited, but remains open to the possibility he's wrong. Most of the book is spent covering the theology of the matter.
1 hour interview with book author: https://cm.patmoshosting.com/videos/dist/micd-2022-07-31.mp4
3 hour interview with book author: https://pintswithaquinas.libsyn.com/aliens-ufos-and-the-catholic-church-w-dr-paul-thigpen
If you want to talk about if Jesus was a time traveler with fantastic technology or an alien with healing powers, etc. then that's reframing the issue.
Either way, God exists outside of space and time. If aliens were spurring evolution and acting like the Vorlons in Babylon 5, then they weren't "god". It could very well be, like God using evolution as the mechanism by which humanity came to be, that aliens were part of that.
Which is getting way ahead of things anyway. I personally believe there are enough holes in evolution that the process existing is unlikely. Not even getting into the possibility of aliens guiding our evolution yet. If that were the case though you are right, it ultimately wouldn't change anything.
I could be God as much as aliens, guiding our evolution.