We did some more research on the hangover soup place and found a YouTube video of our tour guide from back then, giving the viewer instructions on how to get there and the name of the place!

We found it, and it was extremely good. It's called "Hyundai-ok” by the way. In the Namba market. The lady was super nice (in a motherly sort of way), she'd show us how to eat it to maximise the taste. No English though, just sign language.
We returned to the youth market with more success. It was still pretty dead though.

I did, however, manage to find another random scary ghost figure.

We take the train back to Seoul, and its absolutely pouring down with rain. Luckily we managed to find an all you can eat KBBQ buffet! It was also only 15USD per person. This is 3x cheaper than the first KBBQ we went to, and buffet to boot.