The dust shield is between the bearing housing and the support for the ball joints... when I did the u-joints and greased the bearings I damaged one and replaced it... it was on the shelf at the dealer for under $20. 00... there is a clip on the cable for the abs sensor and if its installed correctly on the brake like there is no way that this cable can be damaged by any of the parts that rotate... so its my guess that the cable lips were left off as well... ...
I've done 2 of these trucks so far, and its not easy to do with the rust on the parts... and its easy to damage the dust cover so it won't function... on each truck I've taken a flapper wheel to all the surfaces that touch each other to remove the rust and than coat the parts with anti-seize before re-assembly...
We pressed apart the bearing housing, cleaned the bearings and re-greased them and pressed them back together and re-installed them... .
I'm guessing that the work wasn't done by a dealer, as the tech would walk to the parts counter and get the dust cover and charge you for it... on the other hand... . maybe he'd know the shop should really pay for the part as he damaged it... . and didn't care... .
When you get a minute share with us if it was or was not the dealer...