I don't think so... I doubt any of the solar installation is pegged against that at all. After all, Tesla still has to make SolarCity whole, they can't force SolarCity to take a loss. As a result, there's a limit to discount on the panels anyways. Instead, it doesn't make sense to install solar when there are still so many routes to flush out. Now, PowerPack totally makes sense where they get hit with high demand charges as capex allows. That's mostly in the most congested Superchargers with the highest peak rates and demand charges that also have the space for the PowerPack installation.
The deal would not be structured at a loss. It would just be stupid to be buying millions of solar panels from another manufacturer.