Return from the Underworld/Succeed pt.1 by Locke's disciple

Like all my theories, this one's long. I just can't make a good argument with only two paragraphs.

RETURN FROM THE UNDERWORLD pt.1

The Underworld (afterlife) The final frontier. These are the voyages of- (just joking) The entities of the Island have access to this place. Jacob, MIB and the Monster. I'm theorizing that MIB and the Monster are two separate, distinct entities with "common interests" and so they reluctantly collaborate together, but they have something they're in direct competition over as well and have different modus operandi to obtain this goal (Not the Jacob vs MIB conflict, its something else I'll come back to) I would loosely compare their dynamic to Jack and Sawyer. They also have common interests, reluctantly collaborate together, have something they're in direct competition over, and employ differing methods to obtain their goals.

Charlotte Malkin died and crossed over into a realm "in between" places and relays a message to Eko from Yemi that she couldn't have known without speaking with him somehow. She's not a fraud. She did what she thought she was supposed to do because she was told to. The in between place she went to was the Island. A nexus for many things but I'm only focusing on the life and death aspects. "The land of the living" and "this place is death." Her experience was like one of the bizarre dreams Eko, Locke, Claire, or Charlie had. By this time Yemi's corpse was in the beechcraft and his essence was in the Underworld making it accessible from the Island for MIB to impersonate and speak with Charlotte Malkin. Just another task for the loophole. The set up for Eko to be enticed when he later meets Yemi.

The corpse was still in the plane at this point, unlike when it was gone and then the Monster impersonated Yemi. We see a body in the crate and Locke's body walking around during the same time in The Incident. Smokey seems to have to take the corpse away, MIB seems to not have to do that. Ben's torch went out as the Monster arrived but relighted after the Monster retreated right before the apparition of Alex shows up. The Monster extinguishes flames in it's proximity. MIB doesn't as he walks around holding a torch. Similar abilities, common interests and differing modus operandi.

In the autopsy Charlotte screams "Let John Locke go (on)!" as she returns to her body. Locke had crossed over to the Underworld when he died from being pushed out of the window but was brought back to life by Jacob. "Let John Locke go (on)!" was a message from MIB. In a sense by resurrecting him Jacob is replying, "No. Sorry. I can't. He's got too much work to do." However, dead is dead and you don't get to come back from that. Jacob broke the rules. He changed the rules. Locke was returned from the Underworld to serve Jacob's purpose. MIB exploited this violation for his own purposes. "I see you found your loophole." "Indeed I did." He was the cause of his own death and dismissal from power, by causing the things he set out to prevent.

MIB being the one who judges Jacob. The Monster is the one who judges humans.