I have a feeling there is still a degree of your knowledge of Japanese involved in this. If I posted an equivalent amount of Irish do you think you could extrapolate enough about how the language works to determine whether or not a sentence was nonsense? If not why do you think this case is different?
You may be right! I think my Japanese knowledge really only helps recognize certain vocabulary, but it's hard to say definitively. Would be interesting to compare if some similar pamphlet existed for another language.
Particle omission is a thing in modern Japanese, so it's plausible that it also happened in Yokohama pidgin too; especially since particle/preposition omission is a feature sometimes observed in the transition from a standard language to its pidgin variant.
It's certainly not the lack of particles that is throwing me off, but the lack of any time indicator, which I believe is integral to achieving the meaning of "did someone come by when I was out?" Otherwise, how would you differentiate between stuff like "is someone here? I was out" or "is someone here? I'm going out" or any combination of tenses. Again, if it was an agreed upon phrase then there's not much more to say, but it feels like the other stuff has a somewhat clear logic even within the grossly simple grammar.
Kind of back on the main topic, I really love their word for light house:
"fooney high kin serampan nigh rosokoo"
fixed to modern romaji:
"fune haiken serampan nai roosoku"
Apparently "serampan" comes from the Malay word "serampang" maybe, and is used here to mean "break."
Anyway it comes out to: "boat see break no candle" or "candle that spots boats and stops them from breaking." Quite the description!