I just want to say that if you're working on Sherlock Holmes, that's great! As you may or may not be aware, I've got a project to translate as many early Famicom games as possible. This would be one of the few remaining, from 1986 and earlier, so keep up the good work!
I'm not "working on it" so much as just translating the script, but yeah, hopefully this will be another one off the list! I am aware of your efforts and highly applaud them!
As for the script, I'm a bit tied up today so can't sit down and look in detail. Have you played through the game to find these lines, or watched a longplay where they might occur? Context can really help. I've changed translations late in a project when I realised what the context was going to be.
There is a long play, but as is often the case with Japanese games, the player skips the text so fast it's essentially worthless. I have considered playing the game a bit for some additional context, but I haven't done so yet. I'd also just as soon move on to my other scripts.
I've had the same experiences though. I always feel I get better with each script, but even my latest scripts I've translation checked and gone, "Oh, I can't believe I almost turned in/released the script with that line like that." Double and triple checking is necessary, and playing in context is important, if it's not done by the translator, at least by a script editor.