I asked around some people who know. I know a little myself, but it's always interesting to follow up some details.
The original logo was created by one of the guys in the German forum - Frido, who set up one of the original UK group meets at NSU while they were still producing A2s. I'm sure there are a couple of people still around who were there.
This is back in around 2003; it's been around since I have (and I joined that forum in October 2003, 6 months after this one). The logo has survived three different platforms and several VBulletin upgrades, is a favicon - if you're not using https - and is also now in SVG format on the Wiki.
So: no, the German club were first, and by quite some distance. Or at least that's how I see 10 years previously...
- Bret