The local rebels had been trained as well as they possibly could be and were given sufficient arms and munitions to storm the capital.
Warfare in former colonial regions was much simpler than in Bruno's past life. There were no massive stockpiles of automatic weapons and shaped charges handed out en masse by ideological governments fighting proxy wars against one another for resources.
Nor were there vast colonial stockpiles of advanced weaponry left behind. Most colonies had gone the way of the dodo before anything but heavy machine guns and bolt action rifles were standardized across modern nations.
Bruno had effectively dismantled the capability of colonial chaos, as they lacked the infrastructure and education to produce any weaponry of value on their own. Meaning every bullet fired and rifle wielded was either a relic of a bygone age or a refurbished piece of machinery with an end date and a supply line that could be effectively cut off at any given time by Berlin.
