Dude, how do I get it thru your thick skull that that is a development blog? It's trying and testing a variety of things. They may have put it in a test van, or even a customer's van. That doesn't make it an offering, or put it on a build/option sheet. They don't publish a build or spec sheet on their site. Probably because it's changing all the time as new equipment comes available.
Somehow, since 2012, they got past the issue of using the second alternator with Mercedes. What that solution was, we don't really know. We don't really know for sure if it's resolved even. Perhaps Advanced and Roatrek are just proceeding anyways. Someone with some actual knowledge of the subject can comment on that.