!! spoilers!!
I thought it was Father Soul - I was really certain we couldn't investigate the podium because Hip's hand would be there, and he did not provide an alibi. He is also in the perfect position to corrupt not only all of the sisters but the entire town away from God, but maybe demons in this world are less about corruption and more about just brutal murder lol. I had a feeling he might be a red herring for these very reasons - But! I believe we are meant to come to the understanding that it is Sister Folk because;
1: blood is thicker on her side of the room and trails away (maybe Hop would be next?)
2: She takes the gun from us but gives it back, trying to buy us into believing she is innocent under the guise of being 'trustworthy', directly saying that we should know whose side she is now.
3: The alibi she gives us states she's been in the garden all night, but when we investigate the very bloody pot, I believe she goes into further detail about having pulled stuff from the garden into the main room, which would be why there is dirt everywhere.