MB has passed the emissions testing and certification. However, the EPA has asked for a large amount of additional information from MB. I believe it includes software source code etc. MB has rightly questioned this, as the data is proprietary/trade secret, and the EPA may choose to divulge this. So MB is concerned with the data being lost to competitors through corporate espionage.
Don't know where you get your information, but the California CARB just certified the 2020 Sprinter V-6 diesel last week, March 4th. It still going to be awhile before the 2020 Sprinters are released.