Well, to be honest I did use your guide! The updated one, I mean.. it really helped me on the part with the aqueducts, it did not come to me that their +2 adjacency could count towards hansa.
I couldn't place canals or a dam and that's why I went with aqueducts.
...
As for runaway civs, yeah... Mali. Nobody beats Mali on the gold game. I mean, you can try if you like. You're welcome to fail. Ever tried being economic allies with AI Mali and sending a trade route?
Basically, if Mali is in the game, send spies there to siphon gold.
Kongo actually does pretty well in gold... If anything due to not having a production malus they can easily make more gold than Mali due to getting more cities up and overall having better early game infrastructure in place with some great merchant bonii. Mali does have that purchase discount going for them though... As well as being able to purchase districts without Reyna.
I've played both and will say they are close but after removal of harvest pantheon I'd say Kongo is easier to win with. The early faith only is useful if you get classical golden age and that is so hard to do with Mali (production malus really, really hurts now that deity barbs are as they are... Your routes are easily plundered and you take forever to get 3 archers)