2004 Jeep Liberty drivetrain & axles problems

My husband is a mechanic. He and his employer were trying to maneuver a 2004 jeep liberty into the work stall from the parking lot. The jeep had a broken ball joint (a condition that they later found was under recall notice) and would not steer, so my husband was guiding it with a floor jack while his boss was behind the wheel, braking when necessary to help control forward momentum. The vehicle was idling. This is standard procedure, one carried out many times by both men.

Dt: the contact stated that while driving 2004 jeep liberty the left front driver's side wheel fell to the right and was hanging on by lugs:nuts. Upon inspection the upper ball joint and the upper control arm and the axle broke. The vehicle speed was 20 MPH. The vehicle was taken the dealership, and the dealer ship offered no explanation as to why this happened. The contact called chrysler, and was informed that there was no recall. The vehicle currently has only 30,000 miles on. It.