How about something two weeks, round trip? That puts him somewhat into the United Earth and lets him start observing from the inside. As long as he can playact really good and imitate the general habits of the Natives, it'll be to his benefit; he can come into contact with part of the smuggling ring that leads back to Exsilium, if you'd like. There will be information ports in the Civili Buildings, though tapping into them will show they're on the receiving end of information bursts, with limited capacity to communicate backward toward the origin point.

Pretend that makes sense with me, por favor, they just have less access on the city side than they do where the information pushes originate!