He's right about the Yaminami thing. Also, i think Kondou was assassinated after the shogun resigned. (So at that time the shinsengumi were considered as outlaws)
The shinsengumi was disbanded after the boshin wars. I'm pretty sure Hijikata, Shinpachi, Saitou, and Sanosuke all survived that. Hijikata and sanosuke died shortly after and Shinpachi and saitou lived to like 70.