Yes, a 2005 ECU can only be replaced with another from a 2005 CRD.

The VIN can be reprogrammed into the ECU but you will need the Chrysler DRB tool to do it.
The ID’s from the SKIM and ignition key also need to be programmed into it.

A dealership should be able to do this if you can get yours towed to one.
Or maybe you can find someone on this forum who can do it.
If you ship your ECM to someone they will also need the SKIM, the key, and the programming code for the key.
You can get the code from a dealership parts department if you provide them proof of ownership.

And yes, I’ve been through this before.

Sounds like it might be the gateway module.
It’s located on the frame rail, below the battery, next to the AC compressor.
Check for corrosion and loose or damaged wires.

These key words: Serial Link External Failure

Kinda indicate a problem with the gateway module.
But I’m not the expert in that area.

So keep checking fuses and wires.

Avoid 'rebuilt' ECMs. They're often sent out cleaned up and untested, so are as much of a gamble as a used one from eBay, etc.

Look for broken wires. They're really common on CRDs at this point, and could be causing the symptoms you're describing.

I went through this last year. What was believed to be a fried ECM turned out to be a number of wires underhood that had lost their insulation and were rubbing on conductive things. Ended up returning an ECM and an FCM to the sellers as a result.

Also, if the guy you're working with 'thinks' that he 'might' have touched the positive cable (and I'm not even entirely certain what exactly that's meant to describe in this case, but shorting electronics to earth is generally a bad idea) you may want to find someone else to work with.

Few more things..original ECM and its burnt spot on the board is pin 2,4 and 6.. The main grounds.

I'm on my 2ed replacement ECM, my only code I have is the dreaded P2294 Fuel pressure regulator 2 control circuit open. Tested continuity from end to end, no fault found, like no resistance.

Cranks but no start.

Tested continuity or tested resistance?
no resistance = no continuity = open circuit

I had a bad fuel rail pressure solenoid.
The solenoid itself had a intermittent open circuit.
Passed all resistance and continuity tests.

First, lets make sure we are talking about the same solenoid.

Its the one at the back of the fuel rail, correct.

If I understand the test correctly, you jumper the two pins that would connect to the solenoid and that should create a short and set an appropriate code.
But that doesn't necessarily mean a bad ECM.
That could also mean a open circuit.

I've dealt with plenty of connectors on this engine that created intermittent opens.
Made diagnosis very difficult.