Curt,
As far as a test lab, I've had good success with Celestica in the past.
As far as the testing you need, if you are doing FA on a BGA, X-ray is nice to see if you have a problem, Dye & Pry is nice to help understand the location and scope of the problem, but you really need cross section analysis (SEM/EDX) to analyze the failure mechanism. Skipping the cross section will save you time now bust cost you much more time over the next month.
Pete