Had a similar experience
with my '94 S500 cpe. About 2 yrs ago, the infamous "CE" light came on. That started me down a road that ended up with my Mercedes page w/ info on all of the electronic systems.
The original part number was: 015 545 61 32 with a '93 date code. I replaced it with a junk yard part (from NYC) with the exact same number for $200! The only difference was a later date code of '97. Works fine even today.
The dealer's bs about "not recognizing the camshaft. . " is just that! The DI module (that's a better way of indentifying it) has a connector "2" which is the crankshaft input. Connector "B" is the input from the camshaft sensors. Check my page (www house below): MENU #5 decribes everything about the critter.
To find parts check my page at the bottom for sources of used/new parts.
dpetryk: you're a man after my own heart. Have been able to fix most MB parts also. At least I try. Glad to know that there's someone else who likes to try.
Regards . . . . JimF
'94 S500 Cpe
Visit my Mercedes Web Page