There are no problems in Cicero; whenever there is one insolent enough to come near the surface, the firm hand of the Roman consul and imperator comes down and bends it under the yoke of his authoritative language. The result is impressive: Cicero is one of the most quotable writers in the whole history of political ideas . . .
The point is, Voegelin doesn't "dismiss Cicero." He takes his testimony fully into account, and sources back to Cicero when he does it.