[upflying]

Couple of photos of a partial head on. Due to driver incapacitation, a white Ford Windstar drifted acorss the solid double yellow line and stuck on on-coming MBZ C230 head-on. Both were traveling at about 40 mph prior to impact with no evasive action taken by either belted driver. Both vehicles rotated counter-clockwise after impact and came to rest in opposite directions.
Occupant kinematics caused the upper body mass and head of the MBZ driver to become exposed through the drivers window. The exposure caused a fatal head injury to the MBZ driver.
Stiffness of vehicle structure is the enemy in collisions. Modern vehicles are designed to crush on impact to increase the survivability of occupants by absorbing energy. Essentially the car sacrifices itself to save you.
Partial frontals involve collisions with stiff structures such as suspension mounting points. The MBZ is promoted as a safe vehicle and differences in safety engineering can clearly be seen in the increased deformation shown in the Windstar.
Had the MBZ driver not become partially ejected, this would have been survivable.

 

[upflying]

Also, do you have a crash report to support that the Mercedes driver was wearing a seat belt? (Or any of the other data you present, for that matter.)

No side airbags in the MBZ. I took the crash report.

 

[upflying]

That is an '02 MBZ C230 Sport Coupe. You are correct it does have side airbags.
Since the initial impulse was a frontal impact there may not have been enough energy for the airbag module to deploy the side bags.

Crash reports are confidential except to the involved parties and attorneys. The law is here.
http://www.dmv.ca.gov/pubs/vctop/d10/vc20012.htm