I am a certified member of the Men In Black, but on balance, I think Mistress probably should've been in the bottom three over Sasha last week. Sasha's routine was patchy, but it definitely had more successful funny moments than Mistress's, who sort of just stumbled her way to a half-baked punchline.
That being said, from a production point of view, I can see why they did it. Mistress had already had her 'vulnerable' moment last week, and Sasha had been racing ahead, so it was time to 'make her human'. Coupled with the fact that Sasha's lower placement was basically being pinned on Anetra's absence, and the fact that it wasn't even discussed in Untucked, they basically gave Sasha a 'low' to balance things out with barely any stigma or threat attached to it.
I find it such a kii that, supposedly, Mistress threw such a tantrum about not being able to lipsync to 'Single Ladies' in her dress and that 'they may as well just sent her home now' that she forced production's hand into making it a Malaysia/Salina lipsync instead. It was clearly meant to be Mistress/Malaysia, to round off their arc. I feel bad for Salina, but that's pretty iconic.