I have a 2007 Lincoln
First, I wouldn't be at a dealer
I mark all my drive shafts, as installed, and take
them to a driveshaft shop that,makes or repairs them
I have ALL driveshafts balanced
I have a Lincoln LS ,so I'm guessing your
newer MKZ is front wheel drive ??
Having once owned a trans repair shop, your
transaxle ,if that is what you have, will have to
be stripped clean, to do the bearings your talking
about
On a rear drive, such as my LS, you still have to
remove the rear differental case and strip it, for
brgs
The $700 sounds like a dealer fishing for a solution
to a rear wheel drive vehicle with a vibration
They try a new drive shaft,why not,only your money