How could someone answer this question? Does a 'no' mean the pope is wrong? I don't think so. These aliens could be godless or soulless creatures sent here to test us. They could have something incredibly different as their religion, nevertheless created by the Catholic God to suit them. Perhaps when Jesus incarnated on their homeworld - as a gelatinous fungus like them - they accepted him or her and did not kill him. Who knows?I think you missed my point just by a hair, but you're very right.
What I'm saying is this:
Suppose some aliens did land on earth in a space ship. Would they know about the Judea-Christian god, have bibles and rosaries? Yes or no.
Given the crosscultural issues, it would likely be very hard to even resolve the issue for a long time, I would guess, if it were ever resolved.
An interesting question is WHY NOW?
Why did the pope decide to take a position on the issue?
Are we about to hear something from one of our governments?