Maybe............

May be limited to removing the plastic splash pan and peeking. May be possible to see if a connector is dangling. Pulling the bumper cover isn't difficult, but you want assistants so you don't ding it up. You have to hold it almost in position whilst hooking everything up. I'd guess the mechanic puttin' that part back on realized he didn't have enough hands to hold, maneuver, and plug stuff in. Or maybe it was gettin' near his chowder time.