I highly recommend you do not rev your engine in idle at such high RPMs, especially longer than a few seconds. Clearly the rev limiter kicked in to prevent engine damage. If you drove in gear and reached those RPMs, there shouldn't be violent shaking or rev limiting until you hit 6k RPM at which the car should change gears. Do not test at idle...
God, yes, I cringed when I saw your tach.
Keep the RPMs down, extend the life of your head, head gasket, and transmission. Your car is expensive to maintain in perfect condition, no need to up-rev it; it's an S-Class MB, not a hotrod!
Salt Lake City, Utah USA
97 S320, 94,300 miles, low revs, between 2-2,500 RPMs.