I can't say the helmet does nothing. I can only say that they, perhaps inadvertently, produced set, setting, expectation, and a small measure of discipline. Note, again, this is the same mechanic by which psychedelics can produce experiences strikingly similar to samadhi--with DMT (the only known human endogenous psychedelic chemical) being the forerunner in similarity, in my experience.
It should be noted I used their 8-coil Shakti device, not the "God helmet" and not it's 16-coil Shiva consumer counterpart. I lost interest after 4 or 5 sessions, although I did (in retrospect) experience 2nd jhana strength tactile charism once while "using" it. This was before the GWV educated and shared their radiant presence with me.
While this is interesting, it likely constitutes as idle chatter or self-indulgence to discuss.
However, I think it is important, as members of the only known comprehensive meditative absorption sangha currently, that we should be aware of these avenues through which future proto-mystics will come. You will note this in the case of your friend
Any further discussion will probably need to be moved to a different or new thread. I apologize if I have caused this.