Finally got my hands on a copy. Skimmed through the highlights. Seemed like an enjoyable book that could have been better had it been longer, or had there been another book.
My only other thought, being the poli-sci geek I am:
Why did the Special Representative of the Confederated Martian Colonies, a sovereign and independent state, sign the Federation Charter when the CMC was not one of the founding Federation Members?
The only thing I can think is that he signed as a non-signatory witness or something.
They probably witnessed the document and thereby were granted some protectorate status with representation on the Council but not necessarily any voting on Federation matters.