If Chevy wants to court the VW diesel drivers they need to throw a few more bones out than just the diesel engine. If no wagon, then at least a hatch and a manual transmission. If no manual transmission, then at least a more sporting and responsive automatic. The DSG is a pretty outstanding transmission and VW drivers love it. ****, I love it and I would never own another VW.
The good thing about TDI owners is that, as much as any group of owners, they mostly will understand the peculiarities of diesel engines. In other words, they are the perfect customer base. As with their TDIs, they will especially appreciate the fuel economy and torque. And they'll do so without bitching about DEF, about the "noise" or about the lack of super-instantaneous power. Thus, I think Chevy has a waiting market if they act wisely, and act quickly. Advertise the **** out it, not just when it comes out, but over time.
For what it's worth, I didn't buy my Cruze CTD because it was a Chevy. I bought it because it was a diesel; I specifically sought it out. TDI owners are not just drivers, they're enthusiasts. They're enthusiastic about their TDIs.