The correlated Kinematical Transfer Ionization channel cKTI in fast 4-body (p + He ⇒ H^o + He2+ + e) processes has been used to probe the highly correlated contributions to the asymptotic part of the He grond state wave function. In this reaction one elctron with controlled initial momentum (2.5 to 7.5 a.u.) in the He ground state is kinematically captured by the proton at large impact parameters. The measured 3-particle final state momentum distributions show features of a well-structured three-particle momentum wave function. We conclude the cKTI must almost exclusively proceed via the highly correlated and, virtually excited, non-s² contributions in the He ground state.