Its a government agency, not a company. What the admin gains is deflection of responsibility for the problem and a continued career in governement. If they had to accept responsibility it might terminate their career, so they chose to terminate his instead, i.e. scapegoating. This probably isnt the first instance, its just the first one that came back and bit them in the arse.
I would be interested in actually reading the performance review though, it might give some insight into the problem, as well as the performance reviews of the admins involved and the guys predecessors. Im betting there is a paper trail showing a pattern of scapegoating or at the least poor hiring and management practices.
When things go wrong, blame the people making the decisions, not the guys following orders.