I had written a brilliant piece to respond, but I also opened a second window to this thread so I could refer to the quotes, and in the end the system lost my post.
You got a very good deal. The other quote was about a grand higher than what I would have charged, I think. (and I would have used Ditra). The 2nd quote guy was not interested in doing your job, (probably). that price is about 2x what I think it could be, plus he wasn't going to install the CBU correctly. His backsplash price makes sense though.
It's hard to get good work at an honest price these days.
TILE GUY - retired- TROY, MI - Method & Product suitability consulting.