[X] No One. This information is both important and dangerous and it has already gotten the Night killed from what you can tell. Keep this information to yourself until you can act on it.
[X] The Golden Knight. The Golden Knight and his followers are already engaged against the Consortium and you have tentatively positive contracts with them. They may be criminals, but you can point them in the direction of the Consortium's leadership and the Night's killers.
[X] The Ritual. You will use the ritual to keep out of harm's way. You risk both the ritual not being successful and missing out on details, but it would be safer and you lessen the risk of running afoul of whoever took out the Night.