Sorry about the truck, but glad everyone is safe, that's all that matters.
As far as replacement. All you can do is hold out, and really, no one knows what's going to happen with the EPA.
Very interesting.. seems like it's 3rd party company, not the government wanting to test the truck. Probably looking for hard evidence to make some $$$$.
Nothing official, and they would never release that information.
Also, the ones that join forums are usually joining to say they have a problem, not say how great their truck is running. Many, many EcoDiesels out there that are having no problems.
Welcome!
Since you're running GDE tuning, I would contact them and get their opinion on the sound to see if it's something they have heard before. It could be a bug in your tune file that has a little to much timing, etc.