I dont think Tilt is trying to say that a god or ultimate source idea is not provisionally helpful for some people. Correct me if Im wrong Tilt. Its just that no such idea is congruous with traditional Buddhist teaching. In my opinion it is an acute misunderstanding of Nagarjuna to think he promotes any such idea or leaves any logical room for it in his reasoning.
"Beautifully taught is the Lord's Dhamma, immediately apparent, timeless, of the nature of a personal invitation, progressive, to be attained by the wise, each for himself." Anguttara Nikaya V.332