After washing the shelves I was left with a white haze on SS. Tried some Stainless-Steel cleaner spray, but it did not clear it up. I suppose only BKF will resolve my issue.
I think the comments are true that with enough time and effort you can bring those back. If that grill were other than a Platinum, I would suggest trying the Rit Dye technique and making them black.
If somehow you can't make them look good by cleaning, you could also paint them the light gray that I believe is called "Stone gray." Going with an almost identical color will buy you time before you would have to repaint. To me, it would be worth it if you can't get the stains and fade cleaned and shined up.