Seems to me that the Anthraxer was a rookie, got a small sample of weapons-grade material and tried to reproduce it, not realizing (as any "scientist" familiar with the weaponization of anthrax would) that the milling and coating would not be transferred to any successive generations produced from the original sample. This second-generation material was sent to media outlets, with fairly minor results, then the remaining original material was sent out.
The big question is where did the original sample come from?? It still looks like Fort Dietrick.
"The big question is where did the original sample come from?? It still looks like Fort Dietrick." Originally? Yes, quite likely.
But the question before the house is where the most recent iteration of the original sample came from...