Because he was at Chicago, but that doesn't change that there was a meeting for Battle Ground. Harry got smashed in the general vote and then in the senior council vote.
But Harry didn't go to it, the meeting happened right after, Eb and LTW were still in surgery.. I don't think on this type of thing there is a general vote, if there were, there would have been back in Summer Knight.
Here is the the quote from Battle Ground page 372
"The Senior Council voted in emergency session, while Listens-to-Winds and McCoy were in surgery."
Carlos mentions "witnesses" that Harry killed human servants of the Fomor.. Harry argues back that Carlos knows perfectly well that they are not exactly human..
Carlos answers;
"Doesn't matter what I think," Ramirez said. "You know how broadly they interpret the First Law."
It didn't matter what Carlos thought because he doesn't get a vote in the matter.. It is about how "they" meaning the Senior Council interprets the law, and the vote was unanimous, that is, with at least three members not present. You might call it pay back from Langtry as well, with his "proxy" votes he attempted to convict Molly as well, except Harry stopped him.. In the case Carlos either wouldn't or couldn't, and had started down the road before when he put the tracker on Harry at the beginning of Peace Talks.