Whey protein is ALL THE SAME. it either makes that label requirment or it doesn't. You never mentioned you had lactose intolerance so there must be some preservative or flavoring that you are allergic too. get a different brand.
isolate is just overpriced whey... 90% protein rather than 80% protein. if you are worried about 2 grams more per serving (ruffly) then use a little more. saying that someone must use an isolate over a standard WPC is assinine.