There is one other individual who has mentioned they are currently talking to this company:
Wondering if anyone in Virginia has worked with American Home Contractors. I have been waiting for an opportunity to get a quote on a solar tile roof vs solar panels and replacing our roof with standing seam roof. Finally got some progress when tesla solar pushed me over to AHC to get a quote...
teslamotorsclub.com
I am not sure if there exists a list, and I would not be surprised if there aren't any others in the area at the time as it seems like Tesla currently does not have too many authorized installers. AHC is the only name I've heard, and only from that thread. I believe all of the completed DC-area installs, including ours, reported in this forum so far have been direct through Tesla.
Most likely, you will get a better price from Tesla and better service from AHC, and it will be up to you to decide what the better service might be worth.