Consider the following premises. There is at least one x_7 for which x_7 is bored if and only if x_7 is a janitor. For all x_7, if x_7 were bored, then x_7 is a janitor. 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 were a janitor does not imply that x_7 is bored.
That contradicts the premises. Therefore the answer is no.