I wonder if you really believe the BS you just spouted right now. If there are is no tribalism then why are there militia movements all over the place? Blaming Zuma for destabilizing Congo now? There is no unity or nationalism in Congo and there won't be anytime soon, it will be broken up eventually. Lingala is a lingua franca so of course other ethnic groups will know it, same as different Nigerians communicate in English so your point makes no sense.
Militia movements (specifically rebels in the Eastern part of the country are from Rwanda/Uganda) are mostly FOREIGN hence my statement Congo has a problem of foreign aggression with the complicity of its political class. If it's not deaths from foreign influenced rebels in the East, it's state sponsored violence (security forces) but very SELDOM ethnic tribal violence that you find in other parts of the continent. Refrain from talking about things you know nothing about.
Lingala is spoken mostly in the capital Kinshasa and not the official language of the nation. Let me use an analogy for you English is to Nigeria as French is to Congo hence the comparison between Lingala and English is not a valid one (All Nigerians have to speak English as it is the official/administrative/school (academic) language just like all Congolese have to speak French as it is the administrative/official/school (academic) language but not all Congolese have to speak Lingala. Understand?).
The western past of the country close to Kinshasa speaks Lingala, Kikongo and Tshiluba (Kasai provinces) in the central part of the country, Swahili in the Northeast/Southeast of the country (Kivus, Katanga provinces). But you have different ethnic groups who speak languages other than what is predominantly spoken in their large regional blocs making tribalism not much of an issue compared to other African countries.
Zuma and his nephew Khubuluse have mineral rights in the country so they cannot be objective arbiter of the regime in place same as the former President of the AU declared the elections of 2011 fair and free and has not used its bully pulpit to condemn the wrongs in Congo or wrongs in the whole continent basically a useless family who doesn't use their influence for good.