The aforementioned Barbara Hatch Rosenberg. Hatfill is the fourth scientist she has fingered (she changes her story with some frequency).
The others had either AMRIID ties, CIA connections or a Battelle Institute (a purported CIA contractor) link.
Her agenda is quite clear. To force the US into signing the UN's Anti-Biological Warfare treaty, apparently by implicating the military/intelligence community responsible for our defense against biowarfare.
From the above links, it actually sounds to me like this woman is getting "two for the price of one". In addition to what you correctly stated, it sounds like she also has a personal grudge against this Hatfill guy for his earlier battles in Africa against Robert Mugabe's guerillas.