Hun, I'm sorry you're still not having any joy. There are two things that dairy can cause problems with - lactose intolerance, and allergy. It's great that the intolerance test came back ok, but it doesn't rule out allergy. I think the allergy is to do with the milk proteins, so lactose free still could be a problem. The good news about dairy allergies is that kids usually grow out of them within a year. But in the meantime I would persist with the dairy free in case that's the problem. At least you will either see an improvement or not, so it can be a starting point for figuring out what the problem is.

Best of luck hun.