It is doubtful poor suspension geometry is the culprit for the broken bolt.
The wheels/spacers sound worrisome. You are stressing the lug bolts which is very dangerous. If the wheel is correct for the car, it should not require spacers. Verify that the wheel is the correct one for your car.
There may be some who disagree with me, but I don't like the idea of spacers. Get rid of the spacers if you can. If you have to use them to get the wheels to fit, install longer lug bolts but your safest alternative is to change the wheels to ones that fit properly.
Keep us posted,
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)