Total IMMO overhaul advice

[cts4b5tt]

Hoooo boy. Hello all.
Just bought a used, non running 2007 S8. The price was too good. The previous owner had a bit of an idea with what was wrong with it, had taken it to the dealer, tried some repairs himself. Obviously unsuccessful.

The Tl;Dr is if I bought a kit of used parts from a working car, same year A8, that includes: kessy, ignition switch, key and fob, steering column module, ecm, cluster, lock cylinder for driver door and trunk. Should the car theoretically fire up and be fine?

The long version: the current state of the car is the sunroof leaked, wrecked the Kessy under the seat. Previous owner was told the issue. Bought a new kessy, had some specialty shop remove the eeprom from the old module and solder into a brand new one. Now, both key fobs lock and unlock the car just fine. One key is locked in the ignition module next to the steering wheel. I cannot remove it (nicely) because previous owner tried a little too hard to hit that release button and destroyed it. Ignition switch does nothing, left or right, everything is dead. The only life I see is if I disconnect and reconnect the Kessy, a screen pops up on the cluster and just says "no key recognized" for about 3 seconds then all goes dark again. Car has brand new battery for diagnostic purposes.

I did talk to the dealer he brought it to, they told him that he would also need a new column, the J518 module. Fun fact, this car doesn't have a normal J518 module like the 6s and the Qs. But that's where the owner decided he didn't want to put any more money into it. And because of the ignition switch issue, it will also need one of those. And of course this will all take towtruck trips and dealer visits that will certainly rack up a bill.

So, there is a kit I'm looking at from the same year A8, it comes with all the parts listed above. From what I've read it looks like if all those parts are replaced it should work. My only concern is that the ECM is from an A8, and I'm sure won't work on the S8. Is the ECM necessary for this change? And could I have my current ECM programmed (vcds or otherwise) to accept the new components? Let me hear all your thoughts!

Also if there's any way to bypass all the crap, I'm open to those ideas as well. Thanks everyone!

[cts4b5tt]

Well, as my situation appears to be relatively unique, I've made the first step. I found a company called Speedometer Solutions, they specialize in VW products, specifically things like this. I sent them both Kessy modules, my steering column and a key fob. They're going to diagnose and repair as necessary, and hopefully get everything back to communicating with each other. Will update this thread as we go!