Plot armor to save an MC is more or less expected, even if you hope the author will at least be classy about it. Plot armor to save villainS, plural, MULTIPLE TIMES is trash-tier writing.
And the Church, well... "So you know how this girl tried to kill her sister TWICE? Well, she's a candidate to be a priest for an event, so...forgive her. I mean, who better for the role of priest? And her sister, WHOM SHE TRIED TO KILL TWICE, is a candidate too, so by forgiving her we're giving her chance AND LOCATION to try to kill her A THIRD TIME. God acts in mysterious ways".
Mysterious ways indeed...