She"s probably still rather upset and not thinking straight, which would account for the style of writing.
It's easier to blame the manufacturer, than realise your baby has an intolerance, something which might make future life difficult, and also that you didn't spot it quicker. Because even though she missed it on the packaging, there has been plenty on social media in the month or so since the change - threads on Netmums for example, and lots of articles on parenting sites. And vegetarian ones, questioning if the new ingredient (fish oils) can be consumed by veggie babies.
I don't think this petition will get anywhere, because it's so difficult to read (long solid text) and as others have said, isn't really clear enough. Because I can't tell if she'd been using SMA before and then new package and problems, or if she was beginning combined feeding for the first time and her baby might have reacted to any modified cow's milk.
I note the idea that a particular brand is 'next best thing' still has traction, even though all cow based formula is much the same.