If the shortest program outputting your predictions looks like a specification of a physical world, and then an identification of your sensory inputs within that world, and the physical world in your model has both a meatspace copy of you and a simulated copy of you, the only difference in this Solomonoff-analogous prior between being a meat-person and a chip-person is the complexity of identifying your sensory inputs.

Firstly, this isn't a Solomonoff-analogous prior. It is the Solomonoff prior. Solomonoff Induction is Bayesian.

Secondly, my objection is that in all circumstances, if right-now-me does not possess actual information about uploaded or simulated copies of myself, then the simplest explanation for physically-explicable sensory inputs (ie: sensory inputs that don't vary between physical and simulated copies), the explanation with the lowest Kolmogorov complexity, is that I am physical and also the only copy of myself in existence at the present time.

This means that the 1000 simulated copies must arrive to an incorrect conclusion for rational reasons: the scenario you invented deliberately, maliciously strips them of any means to distinguish themselves from the original, physical me. A rational agent cannot be expected to necessarily win in adversarially-constructed situations.