Since the fog formed as the funeral started, I will assume you scout out the fog after the funeral. How far do you scout?
The Circle have left you with instructions to contact them should you discover anything. They cast a spell on you allowing you to inform them you need to contact them by snapping your fingers eleven times consecutively.

"I am not sure how they went insane, or even if they were druids. The locals call them druids, but that may just be because they live in the forest or because they are elves. This bunch is unused to sane non-humans. As for Revan, the gods have shown me that I must not directly interfere with his task. And you are right, he could be the death of us all. But that is a chance I am being told to take. And I understand your concerns about traveling to the church but every day I wait is a day that my companions must survive." At the mention of the book, Ashlyn frowns, "Do you speak of the Tome of Strahd? I know nothing but rumors, perhaps Madame Eva knows what you search for?"