Wow. Sorry to hear about your Tricolore. I took the time to read your whole website, and I do empathize.
After spending the last decade tuning VW and MINIs on my own and to some extreme power outputs, I have run across the same story many times. People who turn to ECU tuning/modification to get greater power and performance out of their vehicles usually with great effect, especially so in FI situations. As your situation illustrates, unfortunately when something goes south your story is the natural outcome.
Any major vehicle manuf. is going to null your engine warranty if you touch the fuel/timing/AFR/Firmware, etc. There is simply no way to disprove their position that the mods did not cause the failure. Though I commend you for your efforts with DNA, I suggest you just take your lumps, get your bike back together and enjoy it. Don't waste your riding time, sanity, and sleep trying to fight them in court. You are not going to win.
The MM is a joke when it comes to actually winning in a court setting. DNA will just continue to hit the point that you can't prove, beyond reasonable doubt, that the ECU did not lead to the problem. Unless you can do that no court is going to settle on your side. In the end you will be stuck with your bills, the expense of the repair, DNA's court expenses, and a lot of time you could have been enjoying your rebuilt bike wasted in a court setting.
I hope this is a lesson to those who are new to high performance high expense vehicles. It sounds like "Okd" is not new, but hadn't learned this lesson through personal experience yet just how this falls out. With how are vehicles are truly computer driven, any modification to how that computer works, is going to cost you any engine related warranty coverage. As I wrote, it can't be proven that his altering the ECU didn't cause the ring failure, though by the same token it can't be proven that it did.
I do question as to why you couldn't wait to get the engine tuned correctly with the DP Race ECU? What made it impossible to travel back the New Mexico? They say every "accident" has a sentinel event. In your case, I think this was it. Everything that followed stemmed from not sticking with the very tunable, and warrantied, DP Race ECU and going to an aftermarket one.
Regards,
Joel