If you do the Skinned Tapir quest right away, the butterflies die and moths start appearing. It also allows you to go to the Pond and follow the path, as the butterflies blocking your path are now dead. It leads to one of the more intense scenes in the Hinterlands and worth checking out at least once. It's likely tied to the missing kids, but you can't revisit the church to know for sure.
I haven't found the bones to effect any progression, as it seems like helping the god puts their souls at ease more than the Christian burial ever could.