I've got Napa Lifetime ball joints on my truck and my boss has Moog Lifetimes on his '05 3500.
Both our trucks are fighting this same pull and neither of us can figure it out. Between both of us we've thrown thousands of dollars of parts and labor at these trucks to try and figure out what is causing the pull (rotating tires, checking ball joints, center link, track bar, sway bar links, axle universals, steering shaft, steering box, checking for seized calipers)....nothing we have done to the trucks has fixed the pull.
My alignment shop told me the same thing about the offset ball joints being the solution but I refuse to believe this since my truck tracked straight as an arrow for well over a year with the Napa balljoints untill one day it just started pulling.
One of these days I'm going to go to another alignment shop and see what they can do. There's plenty of play room within the tolerences for them to tweak the steering.