Guess it’s safe to assume that this is the camp of people they left, which would solve the problem of not having to transport a whole lot of people back to SB if there’s just this core group left.
I’m not buying Hook’s act like he was caught in the heat of battle and barely survived. He totally heard about Snow and Co from Cora, so he snuck in there to pretend to be a survivor, to weasel into their group and piggyback on their ride to SB.