If her plan was a defined contribution plan then she would be carrying the risk of investing her pension. Since it is a defined benefit plan then the firm,in this case government, carries the risk of investing the money she has contributed towards her pension.
Just like many firms may have over or underfunded DB plans, they are required to meet their obligations. If the pension funds were poorly managed, then blame needs to be put on the people managing those funds
Yup, and this is precisely why companies that offer retirement plans favor DC over DB. DB plans are relics of days gone by, but public sector DB plans will haunt taxpayers for generations to come.