I am sure he wanted to go there as a commoner and pray sincerely. The only way he can do that is by covering his face. Why should there be any controversy? Celebrities have been known to use burqa on many occasions e.g. to go and see their own movies in theatres and get a first hand response from the audience. In ancient times, even kings would go incongnito and mingle with the public.
It's a different matter that if I were God I would pat Himesh on the back and tell him to go and compose better music 😆
If I were Himesh, I would ask such god what is good music... and I am sure its endless debate because the opinion changes from person to person and god to god 😛