Mark- Yes, my Arrow does have the 2 battery compartment because my model is the short bed model with the permanent rear side saddle skirts. If you TC is the long bed model I believe that the battery box is located higher up and near the water heater, but I believe that it is still a 2-battery setup?
I am most certainly able to run the heater and a CPAP machine for a couple of nights but I am usually running the generator for at least an hour a day if possible while cooking. If the batteries are in good shape I can go a few nights but I am frugal with all other items such as lights, etc to enable me to do so.