Update:
After posting a negative review on their facebook page, with a link to the entire story on my site, I got a call from
David Surguine, who is the new GM of this dealership. The Hixson family fired the old GM and brought in David to fix things. It appears they also fired the SA who 'helped' me.
David seemed genuinely concerned and disconcerted with my experience, gave me his cellphone number, and said he is working to turn the dealer around. He said he's been there about two weeks now, and wasn't aware of my particular experience until I posted it on their FB. He also said he'll be talking with the service manager and the tech that worked on my car to see what the breakdown was.
That really doesn't help my experience, but it is good to know they're trying to turn it around.