As usual, your beliefs do not agree with the facts.
Preston's book is very specific about what happened on the 25th of October.
What difference does it make WHEN they checked the media anthrax? The only thing that is important is that it also contained silicon and oxygen. And since it was just a "crude powder," that means the silicon and oxygen most likely came from lab contamination during the fermenting process. It had NOTHING to do with weaponization.
The media spores contained significantly more silica than the senate spores. Naturally you interpret this finding of a silica additive to mean “contamination” by silicon and oxygen. This is almost akin to saying that a harmless powder was sent that was accidently contaminated with anthrax spores.
It’s called spin.
The facts, however, say otherwise.
It’s always a sure sign that a spinmeister is at work when he is forced to flat out lie about the facts. Such as Meselson does when he claims to C&E News that AFIP released a spectrum showing “only a silicon peak” - when the FACTS show that the spectrum they released was a reference sample of silica.
Preston’s book is a book by an outsider.
My information is from the insider who lived it.