Dometic Penguin II Install Fail

It always pays to do your homework on any issue rather than to depend on a "technician" to do everything right on a repair. A lot of shops have a large turnover on labor so the "technician" that you get may be nothing more than a rookie that is getting his "on the job training" at your expense.
I should add that it is always a good idea to educate yourself as much as possible about any issues with your RV, your toad, or even your own healthcare.
Glad that everything turned out well in the end.