I've only played one side of the story, where the MC betrays Xalapa, so as far as I know the ally gives you $12000 vals before the end feast; I also chose the option to say that I'd like to be compensated when they talked outside the city.
I also know that there are ways to get loads of vals, like
- sacrificing a follower at the Aztec temple; 3000 per follower, but I only tried one so I don't know if that's true for subsequent followers, and your party loses morale if this happens.
- raiding a temple a little to the south of Tenochtitlan (~2000, I think)
- grave robbing, there are graves all around continent; one grave gave me 600 vals, so if that's the average then you'd end up with at least 3000-4000.
- robbing/killing merchants and patrols.
- finding El Dorado (~2000, I think).
That's all I can think of, and except the last one, all of these involve being a dick, so if you don't mind rp-ing like that, you have those options.
But seriously, collecting that much to get an ending sounds too much like grinding, and I loathe when games do silly things like that.
I don't understand why they chose an arbitrary figure like 50000 vals, not explicitly mention it in the game, and then tie an ending to that figure. It's ridiculous. Were they going for a tough love approach? Like, life sucks and you won't always get the ending you hoped for.
Or maybe the "king being unhappy" ending is the true ending because it's a more poetic story, and I can't think of an in-game way to know about the figure of 50000 vals.
Moreover, I think if you play a benevolent MC you won't mind being yelled at by the king because, like I said, the ways to get money are all kinds of awful..unless you want to spend time hunting, collecting herbs to make meds etc. and then do some trading.
Or you can be lazy and just use the dev console; imagine you spent time selling medicine, if you like, haha.
About the lanterns- I used lanterns at that point too, and I felt so smart about it, haha. It does some nice damage as they're trying to get in :D I don't know if you absolutely need them, but I doubt that you would- I am sure there are other ways to do it, I'll have to try it out.
Actually, If you have people who can do poison damage, that's one other way to make them lose endurance before they break through.
edit: sorry for thread derailing.