@Switch Blayde
An omni narrator cannot be an unreliable narrator. After all, the narrator is all knowing. But a 3rd-limited narrator can be unreliable. Since the scene is from that character's POV, everything is through their eyes. They could be wrong.
That's really an outdated notion, based on the term used rather than the style of writing. There's nothing that states that a 3rd person Omni narrator is or even is God like, only that they're able to relate details relating to the other characters. The typical phrasing is "as if he's God", but that's hardly a requisite.
Many novel feature flawed or unreliable narrators, and I've never written from a perspective of a all-knowing narrator, as I personally image each of my narrators as specific individuals, with their own narrative voices, presentation, opinions and biases, though those are rarely stated explicitly in the story.
An omni narrator cannot be an unreliable narrator. After all, the narrator is all knowing. But a 3rd-limited narrator can be unreliable.
Sorry, but I fail to distinguish any difference between those two statements. Either the narrator is unreliable or he's not, which is only revealed later in the story. If I recall, a classic flawed narrator is Dexter, from Jeff Lindsey's series, which was written entirely in 3rd person, if I'm not mistaken.