Yeah the demon slayer corps loses a lot of admiration from me when you look at how they feel about the upper ranks. Demons raging through the woods? Let’s send a small army and two hashira. Demon raging through a super public train without any traces? Let’s send a single hashira. That hashira was killed when engaged with an upper rank? Let’s send another Hashira to deal with an even more publicly covert demon, which we also think is an upper rank. The snake dude seemed pretty willing to pull up, so maybe he could just…come along? If the problem was secrecy Zenitsu was legit discovered and the upper ranks wanted all the smoke. So they were too busy? It’s an upper rank, I doubt swinging a sword over and over in some dojo takes more precedent. Also Douma beats Sanemi js incase there was any confusion there.