The Super Snapshot has never been hugely popular in Germany, as far as I know. I ordered my cartridge from a company called GSK Import en Export from the Netherlands in 1990. GSK could have taken the easy route and just shipped the cartridges with an English manual, but they translated the text into German for what was probably a rather limited market. Kudos to GSK!
After more than 30 years I finally got around to scanning the manual and provide it for download as a PDF file.
Unfortunately the cover of the manual was lost at some point in the past 30 years, but I think it was identical with the cover of the English version anyway.