This shop does not stand behind it's work. Simply stated, Roger refused to man up and accept responsibility for inadequacies. Don't know and don't care if problem was due to mechanic's lack of ability or lack of training, regardless outcome was poor and Roger refused to correct the deficiency or even talk about it.
Accepts no responsibility for workmanship. Go elsewhere, even if he appears to be a 'nice, friendly' guy. You will save your money and be happier in the longrun.