Fort Warden's social check should be automatically successful on day 1.
The text for this town should say "If the Daggerfall Covenant is dominant, or if it is day 1, this check is automatically successful." This matches the other starting towns in Cyrodiil with social checks.
The guilds that start you in Fort Warden are the Mages Guild (A01), Undaunted (A20), and Circle of Champions (A33).