To me, this is a question for the next generation of primatologists. It may be an answerable question for the program the Max Planck Institute is attempting, which would attempt to study all chimpanzee groups cultural behaviours using motion-sensor camera traps. However, at the moment it is really not well understood how culture diffuses between chimpanzee groups. In fact, this is quickly becoming a contentious issue between anthropologists and psychologists. Psychologists claim that we cannot be sure that chimpanzees are as complex culturally as anthropologists claim until we know that their cultures diffuse and are transmitted in the same way that human culture diffuses and is transmitted. They claim that until we understand this, it is possible that what we are observing are simply products of ecology, genetics, and random chance.
Can you look at chimpanzee behavior in captivity and see examples of cultural diffusion?
Well there have been cultural diffusion studies. In 2005 Andrew Whiten conducted a well-known experiment where two alpha individuals were taught two different tool techniques for opening a box containing food. When they were placed back in their separate groups everyone learned that specific tool technique. It is an example of how diffusion could work in the wild. But we have no data chronicling the diffusion of a major cultural behaviour between field sites. This could be because they are so isolated from each other. If that's the case then it would be like expecting humans in the 1300s to be diffusing cultural practices between Eurasia and the Americas.