Just a theory, based on what we've seen up through episode 18.
First of all, based on what we saw in episode 18, I'm 95% certain that the Throne Meisters aren't involved with Ptolemais's CB. There's a slim chance that we don't know something yet, but it's fairly certain. Moving on, CB is presumeably composed of at least three different groups. First is the battle group centered around Ptolemais. You've got the ship herself, the four Gundam Meisters, and the support crew (including the bridge crew and the engineering/tech guy, plus a bunch of Haros to handle maintenance and repairs). Veda is housed within Ptolemais, and formulates the strategic options for Ptolemais's Gundam Meisters. Sumeragi picks from the options presented by Veda, and develops the tactical plan for the battles that she's selected. The Ptolemais and her crew appear to be capable of waging war with pretty much zero contact with anyone else (aside from the need for resupply). Wang never appears onboard ship, but still is part of this group. She acts as eyes and ears on the ground using an agent network to gather intelligence when needed for Ptolemais. She also briefs the Observers on what Ptolemais is doing. The second group is the Observers. So far as we can tell, these are a group of individuals (four, iirc?) who were selected through unknown criteria to act as an outside source of influence on CB's actions in the Earth sphere. The Observers individually only have limited power. But by acting together through a unanimous vote they have the right to veto any of CB's actions. I suspect that Corner's 'aide' is his liaison with CB and introduced him to the organization, hence the comment in episode 17 where Corner says that he's glad he met him. There is presumeably at least one more part of CB. This is the top of the CB structure - the group that has been overseeing everything and making sure that the plan progresses. I believe it's been mentioned that the manga features a base, and it's possible that this part of the organization is located there. In episode 18, Wang's dialogue with Corner indicates that she'd hoped that he had access to information on the Thrones. That would suggest the possibility of the Observers communicating directly with the CB leadership. But she may have merely been wondering if the Throne Meisters had contacted the Observers themselves. The odd thing is that there doesn't seem to be any contact between this part of CB's organization and the other two mentioned. When the Thrones appeared, I would have assumed that Sumeragi could simply contact the organization's leadership and follow-up on the legitimacy of the new Gundams. But that doesn't appear to have happened. It's possible that for security reasons, contact with Ptolemais and the Observers was cut off in order to minimize risks of exposure. But it seems unlikely that there is no method of communication at all in the event of an emergency. CB's overall goal seems to be an attempt to foster some sort of transformation of Earth society. What exactly that is we currently don't know, though CB masks it with it's stated goal of eradicating war (to an unknown extent - it's likely that CB does indeed wish to eradicate war, but only as a part of a greater plan). This leads to a possible difference with the Throne Meisters. Through their actions, the Thrones seem to be attempting to eradicate war. But whereas CB waits for a conflict to arise and then intervenes, the Throne Meisters actively seek out anything that might aid a military conflict and destroy it in a pre-emptive strike. junior
