2001 Mercedes C320 no start no crank

2001 Mercedes C320 No start no crank
108k miles
No fuel pump priming or spark
Key turns to accessories and powers them but in the third step won't crank starter

12.56v on battery
Key locks and unlocks car
5v circuit gets 12v on it instead of 5v
Have installed new crank sensor

Any suggestions on where to go next? Can't seem to find where the 5v is supplied from and minimal wiring diagrams to be found online. Opened up ecu and found the following

12V on a 5V circuit screams ground problem.

Go to the throttle body and measure all six wires, backprobed, KOEO. What are the voltages?

Closest I can get to is the Maf connector.

Tested the red yellow out of the ecu and get .1xx volts so assuming its more ecu related especially from the pics I posted above of the damage around the black board with the number 8 sticker on it

The prom chip (the one with a # 8 ) looks like its missing a leg and that large area with what looks like solder next to it seems to be where it arced at take a closer look to see it a leg was sticking out of that area.

yeah I have another c320 locally for sale for the price the cats on it are worth that runs and drives so looking into picking that up and swapping the front and rear sams with the ecu and ignition

I bought a used ECM from a local junkyard using car-part.com , I took both the used ECM and the ECM to a local TV repair shop since I figured they would be able to professionally swap the chips. It worked... I paid $100.00 for the used ECM and the TV repair place only charged me $40.00 for the solder job.