Backstory
We know, that Todd staying at Frodo's tavern, has an unfinished job for the resistance against Carlin. He was supposed to deliver the banned beer to a secret tavern, at which Karl is the barkeeper. (They got another delivery from Carlin, but it's not part of this question.) When Todd finally chooses to close the deal (and redeem his lavish life on stolen money), he would probably ask Gamel to organize the smuggling. As usual, you'd be the one to do the dirty job.
The Quest
Smuggling is not an easy job. After all, everyone who ever tried to bring some cakes from Edron knows what I'm talking about. It is, therefore, of utter importance to keep the transport secret. So secret, that the package should never see sunlight, or even moonlight. You have to stay underground the whole way!
The Question
I am wondering, if it is possible to perform this task. Can you walk from Thais to Carlin while staying underground the whole way? Please provide a map. If not possible, what are the obstacles? If it can be done, then why this quest is not implemented in the game ?
Rationale
I know that Carlin's sewers are connected to a Corym dungeon, which in turn is connected to the dwarven mines. We can travel between the mines through a hub. Furthermore, one of the mines is connected with dungeons under Mt Sternum, which are connected with the Ancient Temple under Thais. But, can all of these connections be chained together? Can we connect from the Temple to Thais's sewers?