I was kind of amazed when it had happened again, I was less experienced the first time. The second time with new company I was abundantly clear from day 1.
The answer, as always, is to tell them what you want and walk if you care enough about getting it that you'd rather work elsewhere than stay without it.
I don't know, but probably not immediately at least given the situation of not having a manager. If I was fully prepared to quit/be fired in response, I wouldn't be asking HN for advice, because quitting is obviously one option to exit the role.