I have tried to stay out of this, but the home builder analogies got me a bit since I am a builder of buildings and can only say that I have flown across the country to work things out with clients. Nobody is ever completely happy in my business and I expect that.
The reason I say this is that there is no substitute for "face time". Forget the emails, texts etc.
With proper resources I would pack it up, ship it and follow it there personally.
Then I would just have that face time, one-on-one and say "now what are we going to do?" and even stay there to make sure things are right and the way you wanted it.
There is nothing like actual face time, trust me.
Just my 2c