This claim is unsupported by the given citation, in which reduplication is only discussed in relation to a single example from a single language. I take strong exception to my work being cited in a misleading way. In fact, empirical work and grammatical descriptions show that the relation between Ideophones and reduplication is far from settled (Dingemanse 2015), rendering the supposed link to two-slot grammars unsubstantiated. That supposed link is very weak anyway because reduplication is not the simple doubling this account makes it out to be, and especially not in ideophones, which often show more complex reduplicative morphology, as the literature also shows.

Dingemanse, M. (2015). Ideophones and Reduplication: Depiction, Description, and the Interpretation of Repeated Talk in Discourse. Studies in Language, 39(4), 946-970. doi:10.1075/sl.39.4.05din.