The person making the pizza the day I visited didn't seem all that bright, but the manager is knowledgeable, and I once I explained I was celiac and needed the pizza prepared safely, I watched him take a full minute to specifically explain to the guy making the pizza exactly how to make it safely (on a pan covered in foil).
They seem to have just one GF pizza, which uses what appears to be the Udi's crust, but also has their own sauce and cheese on it, which were quite delicious.
— Somewhat
— Gluten-free items are marked on the main menu
— Not Much
— Good