52% hydration? That seems quite low for most pizza styles. "Very little yeast" should in no way over ferment a dough in 48 hrs. Especially a cold fermented dough. The holes look like normal fermentation to me. Vacuum sealed dough? Now that's interesting. The actual full recipe and procedure may shed some more light on the problem, if there is a problem, that is.
52% is what my flour can take. I know it sounds low but I've never had anyone complain saying the dough felt too dry.
Besides, Michael Shepherd uses around 52% hydration for his pizzas, and if I did my calculations right Bruno's NY style dough calls for a lower hydration as well
100% -All purpose flour, 10% protein
0.5% Fresh yeast
a) I mix lukewarm water with yeast
b) I add oil to the water
c) I add salt to flour
d) I use a mixer (spiral hook) and let it run for ~8 minutes
e) I divide the dough and form balls
f) I cover them with plastic film and let them rest in room temperature for 20 minutes
g) I put them in the refridgerator
I prefer vacuum sealing, otherwise I get dry surface. With vacuum sealing, when the plastic film is taken off, the surface is little sticky.
I forgot that I had a leftover slice made from the 48 h dough: