Ah yes, that’s true: not every combination will let you feasibly achieve Environmentalist at the same time as Where is EveryBODY and Silent Assassin. I can see that this may be frustrating, but on the other hand, you wouldn’t be able to reliably complete Unsafe Work Environment at the same time as Brain Detail, Environmentalist, or Where is EveryBODY? anyway – regardless of the configuration. I’m happy you found those little ways of manipulating the infecteds’ routines, though.
Regarding the effects on random targets on the outcome of accidents and found bodies, that’s true as well: if someone witnesses a murder or hears an explosion, you may or may not have an escapee on your hands depending on the configuration. The only way to completely avoid it is to stick to silent kills, and when attempting Unsafe Work Environment, the potential accidents along the escape routes are your friends!
@Beldingford, there’s at least one for every potential target – but some of them may require you to mess with the target first.