This is what came to mind for me as well. GG designations were starting to filter in in the early 2000s, taking some time with many producers. It could be that the wine you had is what is now labeled GG, and that’s the way the distributor sold it to the restaurant (presumably because they can get a little more for it), so the restaurant put it on their list that way.
I don’t think they joined the VDP around then but that might have been the answer otherwise.
Scott, what you got is their best dry wine from the grand cru site of the Rothenberg.
What we then call that, GG or otherwise, is almost a semantic point.
Either:
-they hadn’t started using the GG name
-the wine had a gram or two too much sugar (06 botrytis mania) to be labelled as such?
You handled it well. They were generous as well…
was the wine good?
Santé