The VISL translator is not CG-3 - it's GramTrans, with the commercial vendor being GrammarSoft ApS. CG-3 is merely one of the general purpose langtech tools used in the pipeline. Apertium also uses CG-3.
Both GramTrans and Apertium are rule-based. Very similar technology.
(I wrote CG-3, and work for both GrammarSoft and Apertium.)