@GoshisDead,
That's a good point. That was an issue with Nim Chimpski too (btw ebrown Koko was a gorilla), that it was too sterile and "laboratory" of an environment, not enough social interaction.
And Kanzi picked up the whole image board from his (mom?), he wasn't the main focus but was a baby and picked it up. (Bonobo.)
As a slight aside, a lot of fascinating stuff about human acquisition of language in studies of isolated deaf communities that develop their own sign language. Greatly increased complexity, syntax, and general "language-ness" within just a few iterations. (Since older kids taught younger kids, no full generations were required in the mature->have babies-> teach babies -> the babies mature and have their own babies sense, the progression was fairly rapid.)