The guy OP has been dealing with from the beginning was in fact the sales manager at Vancouver Ducati. His bike was previously backed up into by accident while parked in the stall. The person who did it tried to hit and run him, so it was due to someone else's negligence and completely unrelated to anything mechanical.
OP did not replace the actual headlight unit
the only thing that was changed was an hid bulb.
that being said, having been in the industry for a short while, pre-work bike inspections are commonly done to ensure the customer and shop are on the same page before touching their bike.