The way I took it was that he had just saved Chiko from a dangerous place where her life was constantly in danger. Only now, he's taken her to a place where her life is again in danger. I would think he was trying to save her, as he called her "the real treasure," and any regrets he have stem from her going to a potentially equally dangerous world.

She is amazingly smart. I kept thinking she'd notice poison or something in the food, but I can't figure out at all how she knew the gun would be in the drawer. The Chinese woman was with the two of them pretty much all the time.

One thing should have bothered her. Any Chinese person at that time period saying they liked Japanese people. There's no way someone like that could have existed. Maybe that was Chiko's hint, or our writer was being rather creative with history.