Bunch of rubbish. Not all dogs are intolerant of dairy, I would say that most are not. There is little or no theobromine in white chocolate, and even less in the kind that is used to cover icecream which is the stuff that used to be sold as “magic shell”
I can see why the RSPCA made the comment that it did...they have to stick to “the line” on these things.
Neither the problems (where they do exist) with milk or with chocolate are allergies...the chocolate issue is a toxicity and the dairy one is a dietary intolerance. I have got a dog with a pork allergy and I know the difference!
but Twitter and the Daily Mail, why am I not surprised?