we have a 2000 e320 at our shop. we changed the cats because they go bad and make lots of noise, as im sure you guys know thats a common issue on those engines. after that the engine doesnt respond so well, it seems like there isnt enough fuel. we got the cats from mercedez and pressure tested them. we also did a plugs and wires to get rid of some minor misfire. we have changed the pedal sensor because it wasnt responding correctly. we also tried a different throtle body, and still no response. we have checked for any leaks in the intake. also we changed the MAF with a good one and still no response. all the fuses are good and there are no physical damage on the computer boards. also everything looks great on the data stream. so does anybody have any idea of whats up wit this

 

What is the mileage, the miss fire may have been the cause of Cat failure, I wonder if you checked the O2 sensors. What codes were present when you started? Have you checked the circuit at the Tbody plug? is it actuating at all? If you needed to change plugs and wire have you checked the coils residence? You didn't mention the pump pressure if it is off or fuel filter may be spent.
Patch's

 

the mileage is 101k. the misfire was minor and is all gone by replacing the plugs and wires. the codes were about the misfires and did not come back anymore. the O2 sensor is reacting normal. and the Tbody reacts to the input from the pedal sensor. and the coils are fine because there is no more misfire. also the fuel pressure is 65 psi and does not drop at any time. we also changed the fuel filter just in case and also used seafoam in the fuel system to clean up the injectors somewhat

 

Looks like you covered the bases, if I were stuck this way I would most likely try a cold boot, I know it sounds far fetched, but it might initiate some new data or clear a code not readable to your unit?
Sorry no magic bullet I can think of.
Patch's