I think I replied to you on Reddit but I’ll add it here too.
I made another suggestion for Muisca that would have a musketeer type unit.
As for Maroons, I don’t think a musketeer type would fit a fugitive/guerilla unit. Musketeers are line infantry that fight pitched battles and tank enemy fire. Skirms are more of a fragile hit and run type unit. They’re also weak to cavalry which seems like a unit that would be effective at running down escaped slaves. Lastly, musketeers are already decent at siege so my Retribution tech would be too strong if it applied to all musketeer type units (I’m assuming that would be the tech you have an issue with).