Facebook cannot take the position that they are just a platform and not responsible for the content on their site and then do stuff like this... they are either responsible for all of it... or they don’t take sides.
I agree they are and can be prejudiced about which posts they do due diligence on and which they ignore.
That said, I am not convinced she, Amy, has done HER due diligence on the recording, at least not that she has offered any evidence of outside of the recording itself, which may, or may not be a recording of the person it is claimed to be.