Correct me if I am wrong, but I thought the Jetta TDI still had that BlueTec system as it was a joint operation between several automakers. The reason why its already in the Toureg. The Jetta is frankly quite large, I wouldn't call it a compact anymore. And its size would be more than enough to accomodate the system.
Without that system, I dont think the diesels would pass EPA standards for particulates.