MSPI and Fructose Malabsorption?

My two year old has a preliminary diagnosis of Milk Protein Intolerance and Fructose Malabsorption.  I say preliminary because there has not been any testing to prove otherwise.  We are following a very strict FM diet and avoiding all dairy.  When we trial foods, she almost always has a reaction.  A bad reaction leads to abdominal pain/cramping, constipation, green pooh, undigested food, panic/anxiety, and sometimes even a fever.  I keep asking about bacteria overgrowth and getting shut down immediately without any testing.  The GI tells me she is swallowing air and catching a virus.  That is a bunch of bs.  We saw an allergist and he swears its not allergies, that is intolerances.  They are retesting her (blood test only) for Celiac's but she has been off all gluten except oats for quite a while.  He also wants to do an ultrasound of her abdomen.  

How do they test for Milk Protein Intolerance?
Does this sound like anything other than FM?
Does it sound at all like Leaky Gut or Bacteria Overgrowth?  
What good is the ultrasound?

I am tired of seeing my poor baby sick.  I just want her to be better and to be able to live normally!!!