How do I access the swamp? On the Wiki it says that you just go to the spider cave and then go to the guild... But I've done this several times and so far it hasn't worked :/
The Wiki shows the basic conditions for starting the quest. Therefore, as has already been stated many times, if the quest does not start, you need to visit the bartender and the fortuneteller. Because, with a high degree of probability, another quest has not been completed.
If the Bartender and the Fortune Teller are silent and the quest does not start, you need to send a save file.