It was an '07 E350 wagon (all wheel drive). It's so much heavier than a wagon should be ('built like a tank' - thus the tank-wagon remark). I know that's part of the brand promise (and yeah, I think she fared far better in that wagon that she would have in something else, and the wagon properly 'sacrificed itself'), but still...
It did not have the dynamic seats, and when looking for a replacement, we learned that the dynamic seats change things just enough that the seats don't work as well. And the '11/'12 non-dynamic seats are slightly different (but probably OK - it's hard to tell this close to the accident).
We got really lucky and found an '08 E350 wagon online with enough pictures that we could tell the seats didn't have the dynamic seats. Well, lucky but still crossing our fingers that when it gets here it's all good...
What really sucks is that salvage is a financial decision, not up to any mechanic, and the '07 wagon would have been just fine after repair. All that carbon debt gone to waste (well, at least to some other country where they repair such things instead of forcefully tossing them out... it's why the salvage value was apparently so high.)
And the consequences of trying to rescue a salvage vehicle are set up so that the rescuer will feel that financial pinch.