To meet fire separation requirements for townhomes, you'll need to match one of the approved fire-rated wall assemblies, such as two separate 1-hour fire-rated walls, where each wall assembly is rated for fire exposure from both sides.
Code allows for adding layers to approved UL assemblies...
I would expect that you provided a detail for the joist seat bearing on the CMU. If said detail is dimensioned to the center of the wall then I can see where they are coming from.
However, my firm also gives only dimensions to the face of wall since these are more appropriate in the field...
