Mary's Room is an attempt to disprove physicalism. If an example such as Martha's Room shows how physicalism can produce the same results, the argument fails. If, on the other hand, one needs an entirely different argument to show that doesn't happen, and this other argument works just as well on its own (as Chalmers apparently thinks) then Mary's R adds nothing and you should forthrightly admit this. Anything else would be like trying to save an atheist argument about talking snakes in the Bible by turning it into an argument about cognitive science, the supernatural, and attempts to formalize Occam's Razor.

The Zombie Universe Arguments seems like the only extant dualist claim worth considering because Chalmers at least tries to argue that (contrary to my intuition) a physical agent similar to Martha might not have qualia. But even this argument just seems to end in dueling intuitions. (If you can't go any further, then we should mistrust our intuitions and trust the abundant evidence that our reality is somehow made of math.)

Possibly one could construct a better argument by starting with an attempt to fix Solomonoff Induction.