to be honest it doesnt look bad to me... its pretty similar to my install and the one my friend got as well.. i dont know why you are afraid to talk to the tech at your own dealership. you dont have to go at him like "HEY YOU MESSED IT UP!" just ask him nicely, say that you had hoped the exhaust would stick out more and if there is anything he can do to make that happen.
if you do decide to take it to another place, take it to a muffler shop and have them extend the stock pipes where the clamps go. dont cut/extend the tips of the muffler if you plan on selling it after