Sweet baby jesus that sounds like a nightmare! I work on all my bikes, plus I work at a LBS. Its easy to get another mechanic to test ride a taller bike so we never lower the seat especially since there are people (including me) that don't want unnecessary scratches on a carbon post. Now their wrenching skills...front and rear derailleur adjustments are not that difficult, however, I know people that simply want to ride and either have the money for tune-ups or at least have a free year of them. Unfortunately, big places like that will hire anyone.

and the bar tape?! I'd would never let anything like that leave my shop.

It's great to hear everything got situated.
It's another thing to hear it even happened in the first place.