Earlier quoted context omitted.
Is there a consensus (or most popular) theory for how mind/consciousness would work in the simulation theory? How do things in a simulation become subjects of experience?
Conciousness is an emergent property of a physical brain firing neurotransmitters between synapses, just as an economy is an emergent property of society buying and selling things, or ant colony behaviour is an emergent property of the behaviour of individual ants for example. It's not somehow "above" the simulation, just a higher order of complexity defined by lower-level rules, similar to a glider in Conway's Game…
Maybe it is in an emergent property, but maybe it emerges not just due to the complexities of an individual being, but something else which is just missing from our current understanding and we don't know about.