I don't know whether he has any Iwama background, but Asai-shihan, the highest-ranking Aikikai teacher in Germany, teaches in Dusseldorf. Here's a link:
http://www.aikido-schule-asai.de/
I've attended a few practice sessions led by a senior student of Asai-shihan and I liked it. I think you're lucky to have an 8th-dan in town
.