You MUST understand that "shimmy" is not CAUSED by worn steering or suspension components or misalignment. These things will allow a vibration to be amplified and transmitted. The SOURCE of such vibrations begins with ROTATING parts, almost always wheels or tires.
I would give this a 99% chance of being caused by something wrong with wheel(s) or tire(s).
To begin with ensure that the wheels were DYNAMICALLY balanced meaning weights are used on the inboard AND outboard wheel lips. Second most common situation would be a broken belt or other tire flaw causing excessive road force variation (stiff spot.)
To verify wheel/tire integrity find a shop with a Hunter GSP9700 wheel balancing machine. This machine not only checks for wheel balance but also has a pressure wheel to search for stiff spots. To find such a shop go to: www.gsp9700.com There is a locator on that sight.
BTW, does this mean we now need to change the URL for this site to "www.DaimlerChryslerShop.com?"