Yikes. My roll-on deodorant might occasionally stain my shirt, but it will never burn somebody like that.
I'm wondering what caused the burn? It's surely not the deodorant itself. If it were capable of burning skin like that, even though she was abusing it, there would surely be reports of people with sensitive skin being burned all the time. I wonder if that was frostbite?
If you look at deodorant reviews on Amazon you will see a fair number of people who report a burn or at least irritation after just one application of that particular deodorant. So I have to assume that it is the deodorant itself and that a heavy application of it caused the burn.