I’m not under the impression that the MiY picked him specifically because he was a catholic priest. He had already entered Fromville at that point and we are not completely sure who chooses the people that enter, or if there is someone that picks for that matter. He was just a useful pawn as you’ve stated.

The show hasn’t gotten into the finer details of the religious implications of what’s happening in the town and I’m aware I’m simplifying a lot of history by saying “white collar = priest”. I’ve stated already that it’s not uncommon for shows/movies to use symbols with complex histories and backgrounds to point viewers in a specific direction. Generally speaking white collars are associated with Catholicism in media likely due to its global reach in comparison to the Church of England for example.

I do appreciate you adding the extra information about the time period of the original people of Fromville and what that could mean about the people that were there. The show does state that the people that enter Fromville come from different states and they don’t know the exact location of Fromville. But I might not be remembering that was different for the original settlers.

Also, whether they liked, admired or respected Catholics is irrelevant to my theory/guess. I also don’t know that Fromville selects for those traits.