He pretty much cleared out of the camp and left it to be used as a storage space in the cold season (though whether anyone is availing of that is left open; maybe NPCs at the most)! He... honestly didn't know how to make a camp winter-ready... he just secured everything as well as he could because he also didn't know how to take down a (probably) military-grade camp... sorry, Riou!!

So he isn't staying there anymore, but we can totally arrange for that meet-up anyway! Despite what Hijikata tells himself, he thinks of the past a lot, so he may give Rei that location to both have their shady dealings out of the way of prying eyes and "just to check if everything's still in good order"... (Riou isn't coming back, Hijikata).

Also yes, it's still booby-trapped.