I think there is a 4th scenarios; it is not possible to create concious beings in a simulation. Nick Bostrom builds his whole argument chain on the premise of substrate independence of conciousness, meaning that the mind doesn´t need a brain necessarily. I think we just don´t know enough yet about the brain and conciousness to assume a complete substrate independency. Therefore building a logical chain is kind of redundant, when you can not prove the premise yet.