Just curious but why do you prefer the semolina over the cornmeal? I feel the cornmeal adds a different flavor.
Cornmeal was a 'guess' made in the 1970's by a local TV chef and/or a local restaurant reviewer who were trying to reproduce a deep dish pizza recipe to use at home, and they either mistook cornmeal for semolina, or thought it was what made the dough so yellow at Gino's East (it wasn't).
It's been repeated and repeated in recipes for decades, so now people think corn meal is a real deep dish pizza ingredient (it isn't).
Over the years, the ingredient (or it's semolina doppelganger) has been adopted in some pizza restaurants and used as 'ball bearings' for pizza peels and to add extra crunch to the bottom of thin crust pizzas.
Semolina flour is the same color and has an almost identical texture as corn meal, but is made from wheat.
It's the stuff they make pasta from, and would combine more easily with the all purpose flour.
If you were trying to improve the structure of your dough, which would you use?
In my opinion, neither is necessary to make a decent deep dish dough.
Others will have different preferences, opinions and stories, but I firmly believe that cornmeal has no business being in a deep dish dough recipe. Do what you want. It's YOUR pizza.