Andrasz
We do know that the engines were also overhauled just a few months ago (actually 'rebuilt' is more the word, a D-30 overhaul involves the replacement of practically all moving parts).
The Il-62 accident, at that time, also a national tragedy,
took place also shortly after main overhaul.
The overhauling mechanic did a wrong cut on the turbine shaft,
resulting in shaft shear, turbine overrun and uncontained destruction.
Again, just a possibility, not jumping to conclusions.
The tu-154 aircraft in this case was relatively low time, low cycles.