Hey thanks for playing the game!
The main thing about the doctor is that his memory is gone so whatever he keeps rambling bs. But in those ramblings are clues. Basically he says the opposite of what's true. Also, any general information he gives must be fact-checked :)
Spoilers below: -
If you asked about the flickering lampposts in that area he'll say, "Watch every single one, don't ignore anything" and he'll emphasise it. So that means not every single lamp means something. Only three of them mean something, as the locked door can be opened with a 3 letter code. And he says the bog is safe right, so it's not and you'll die there now. You'll have to progress a bit before knowing how to cross it. I won't say anymore, if this helps and you have time, try the game again and see if you can progress!
Also thanks for the tip about the fullscreen, very helpful.