Our questers arrive at the mountain in rather low spirits, though I can't really see why. Dwarves and hobbits seem to be rather pessimistic creatures by nature.
I could understand if they were worried but to just be depressed seems weird, though completely in character since all they do is moan, whine, complain and bitch.
And wouldn't you know it, the arrive at the mountain just on the cusp of autumn/winter, when the map says that they keyhole in the secret door in the mountain will be visible. What luck!
They don't seem to have given any thought to this fortuitous happening, being pessimists and all. At least they're not moaning about food for once.
They do indeed find the keyhole, open the door and head inside the mountain.