Mafia 101. Disputed Island

The answer to the second question is the following night (thanks, Master). That is, Yashura was infected on the 2nd night. I'm starting to think that Sesame is right, and the ultimate ability in the form of infection from the maniac to Rick happened.
But this doesn't negate the fact that Lyuska infected someone on the first night. Either this someone was cured of the infection by the doctor (then where is our fact of successful treatment? She infected the same person as Zero, and they both got cured immediately?)
or it was the Heroist (but then the Heroist isn't Crow, because Crow would send Lyuska),
or he doesn't have protection against infection, but at the same time, he has enough actions/abilities to last 3 nights (this could be Mann, who didn't have protection against infection but received it as a result of recruitment, and this could be Lee, whose protection was removed before the infection).