I dont find it weird that they didnt know he was there, just a small shack in the middle of a Walker infested area. I do find it weird that he still thinks there is a Sherrif to call. How many more months was he gonna wait to contact the authorities about all these dead people trying to eat him?
No Spoilers since this is just a theory. As far as Merle goes,
I have a feeling that he might actually kill the Governor at some point, or at least try to in defense of Daryl, and possibly get left behind once again. As big a racist POS as Merle is, I dont think he would harm his "Baby Brother', or at least allow someone else to.
As for Andrea, no outcome at this point could be 100% positive for her. She has her day of reckoning to come, and unless she does something big to redeem herself when the time comes, I'm not so sure Rick will trust her too easily. That being said, perhaps than she could be the one to kill the Gov. Man, I know it wont get resolved in next episode, so the wait til February will be a long one.