Oh my, now I see that you made her promise not to research the organization online? I can't fathom that. It might actually help her to realize that she's not crazy in seeing what she sees that makes her so depressed. You have to let her be her and if that means she researches stuff she researches stuff. That's not up to you to decide. To make her promise? After saying that she sees the stuff they teach isn't scriptural? You're putting her on an island, and your non-stand taking self is leaving her on that island all alone.
Ugh, maybe I'm reading into this too much, but I see you reading in your own views and trying to push your daughter in ways that may not be good for her because you're projecting. Again, maybe I'm wrong, but what you're writing is all over the place. That may be because you're literally riding fences yourself. You want her to stay inauthentic and to hide the truth from her unless it comes from you. That's not healthy. This hiding of everything has to stop. It's time for everyone to put their big girl and boy panties on and to have some real heart to heart open talks putting it all out on the line instead of playing games. The fact that she came to you with this says that she trusts you on some level. But the way you're playing this where you let her keep going to meetings even though she doesn't want to go, the way you make her promise not to research, that doesn't sound like trustworthy behavior.