Consider the following premises. For all x_7, x_7 will drink water if and only if x_7 is an astronaut. There is at least one x_7 for which if x_7 were an astronaut, then x_7 is a janitor. For all x_7, if x_7 were a janitor, then x_7 is drinking water. Can we infer the following from them? If we can, name the inference rule being used: For all x_7, the fact that x_7 drinks water does not imply that x_7 is an astronaut.
That contradicts the premises. Therefore the answer is no.