Maybe for the locals? Or maybe a Chinese ship, serving for the German Gouvernment?
I agree with you, the writting looks terrible. But by own experience, I would say, this was written by a Chinese (not European, Chinese speaking/writting guy). My Japanese handwritting will be easily identified as "non-Japanese writter".
I found attached picture (courtesy of Chris Dale, http://www.germancolonialuniforms.co.uk/). Looks terrible as well, isn't it?
BR, Chris