I asked the same question and the answer I got was that there was one c.o. called out in the drawing so it got one clean out.
So short answer my master gives zeros f’s and ordered one c.o. tee because he knew he had to have a c.o. where it was accounted for.
More detailed would be the architect didn’t take into account that there was no way to catch seven carriers to the right of that clean out because we need fall. The drawing called for one drop, one clean out. We had to break the carriers into two drops, but the second cross’ clean out would have nowhere to exit the wall because of the proximity of the carriers and the backing for the partitions that is yet not installed as of these pictures. Little bit of bad planning and little bit of lack of desire led to something we’re not required to put in by code to be left out. I dislike it but it’s not wrong per se. As my boss would say “I guarantee you I(he) will never have to pull one of these toilets to snake it!”