Could just say:
If you accept either privacy of consciousness or phenomenal transparency then philosophical zombies must be conceivable and therefore physicalism is wrong and you can’t engineer consciousness by mimicking brain states.
Edit:
I guess I should've expected this, but I'm glad to see multiple people wanted to dive deep into this!
I don't have the expertise or time to truly do it justice myself, so if you want to go deep on this topic I'm going to recommend my favorite communicator on non-materialist (but also non-religious) takes on consciousness, Emerson Green:
- The Hidden Mind: For Privacy and Against Illusionism
- Zombies
- Phenomenal Transparency
- Interview with Philip Goff, talking about all of the above
But I'm trying to give a tl;dl to the first few replies at least.