You're right: The sources selling it as ''Sämling' are in Germany. It's sold as 'Hybrida' in Denmark and Sweden and as 'Semiplena' in France and Poland. Since there is no exhibition name and no clear preference for any of the three names, I'm happy to give 'Hybrida' pride of place in the entry listing. After all, if it's a Danish rose, it seems right to call it what the Danes call it.
It has been renamed:
Rose (Rosa heleniae 'Hybrida')