Ed, ALL the letters were mailed in Boca Raton. Do not mistake downstream contamination in New Jersey with a "mailing".
And of course this is totally based upon your beliefs. Clearly it doesn't bother you that the letters were all postmarked in Trenton, that a mail carrier in that area contracted cutaneous anthrax, that a mailbox was found to contain spores. You can just rationalize explanations for all this in order to believe what you want to believe. But why should anyone accept your baseless beliefs?
Ed