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Checking the Miners Dry list on the wall map at the case it shows the following completed.

opened Sean V locker
broke through wall
picked up arsenic vial
made fresh coffee
and there is one more bullet point indicating there is one more task but I can't work out what it is, I have put the arsenic in the wardens coffee and put the cup on his desk and the projector is complete, is this another bug or is there another task?
That's what frustrated me in this game - there is no last task. All tasks are optional and it looks like there are 2 mutually exclusive tasks in Miners Dry.

All you have to do to beat the game is collect 20 ribbons which does not require any effort - just walk around and click on ribbons until you get them all.

If you spent 3 hours solving a puzzle and was rewarded with an extremely vague tidbit of story or a snide comment from an English woman commenter and nothing else - well, that's just how this game is.

My brain melted from all the character names and connections, so all this tiny tidbits of information which I got after solving puzzles were just drowned in all the information noise this game produces so I gave up solving puzzles when I got to the village area. And I used notes.