I've not heard that before. Hope it works. How long after the frostbite does it need to be applied? I would think it would need to be quite soon, if not before.
I have heard that applying Vaseline to the comb and waddles before the frostbite will prevent it, or at least allow the bird to tolerate a lower temperature. When we were having lows down to 8 degrees I forgot to bring home some Vaseline, so I used some moisturizing lotion ((Alba Botanica Very Emollient body lotion, unscented original formula -- it's bird safe). It did wonders for the comb of my Dorking rooster. The first day of cold temps I didn't remember to apply anything, and when he went in at night to roost his big beautiful comb was nearly flopped over, and he objected more than usual when I touched it. It was ice cold, flaccid, and painful when handled. The roads were icy and it wasn't safe to drive to the store, so I used the lotion. His comb seemed to absorb tons of it, and I kept reapplying it until no more would absorb. Same with the waddles, although he didn't act like they were quite as painful. The next morning the comb was 90% better, and I reapplied it again before I let him out of his house. That evening his comb looked great, but I continued to reapply it twice a day until the temperatures got above 25 degrees, just to be sure. I don't think he had yet gotten frostbite, but he was probably close.