There was something at the time where all the other airframes in addition to MD-11s that were grounded were inspected and not found to have cracks from fatigue over time, pointing to the UPS plane having cracks from being overstressed as was the pylon in the 1979 crash.
I realize that they found similar stress cracks to the 1979 crash, but I hadn’t heard they were using the same “engine + pylon” procedure that was used in 1979.