Facebook did this to me on multiple occasions. I've reported bestiality videos (a woman engaging in coitus with a dog), suicide videos, beheadings, child porn (a nude 3 year old trying to have sex with a nude woman and a man having sex with a little girl), and a Facebook page that says autistics need to be exterminated. Each time, Facebook always sent me a message saying that the content was in compliance with their community guidelines (I have the screenshots of Facebook's responses on another HDD, so I'll post them if I find them).
Facebook only cares that users are on their platform, which is why
they changed their policy to allow malicious content as long as it's not glorifying that type of content (isn't this what shock sites like Best Gore are for?). If idiots sharing child porn on Facebook to "
spread awareness about it" or "
condemn it" is keeping them on Facebook, then Facebook could care less about the content.