Vital wheat gluten and gluten flour might and might not be the same thing. Read the label and compare how many carbs it has with regular flour. If it's significantly lower or tells your to add the product in proportion to the flour in your regular recipes then it's wheat gluten. If not, then it's bakers flour which has more gluten.

I think there's a misprint in the recipe for the amounth of baking soda, perhaps it means 2 teaspoons which would be more reasonable.