Real-Data Validation and Endogenous Coupling Dynamics of the KA Operational Universality Framework: Completing the Research Programme (OP3, OP4, OP6)

The KA Operational Universality Framework -- established theoretically in Papers 1-2, benchmarked on calibrated simulations in Paper 3, and analysed via renormalisation group methods in Paper 4 -- has remained without real-data validation. This paper closes that gap. Real-data validation (OP3, OP4). We extract F_KA and R(t) from three real-world datasets: (1) MIMIC-III intensive care records (n=1,151 sepsis episodes); (2) USGS Advanced National Seismic System catalogue (Parkfield segment, 1987-2004, n=87 foreshock sequences); (3) MODIS NDVI time series for five Sahel sites (n=5 collapse events). F_KA achieves AUC 0.79+/-0.06, 0.83+/-0.07, and 0.81+/-0.09 respectively, outperforming CSD variance (AUC 0.68-0.74) and lag-1 autocorrelation (AUC 0.64-0.71). The R(t) discrimination criterion is confirmed in all domains (AUC 0.88-0.92). Universal T*=1.0 transfers with delta_AUC <=0.03. Coupling dynamics (OP6). The endogenous coupling equation dC/dt = F(S, Sigma, M, E) proposed in Paper 2 is derived from a stochastic Volterra integral representation of the SDE covariance evolution. In the Markov limit, the closed-form equation predicts exponential runaway near the critical manifold: C(t) ~ C(t0)*exp(-lambda*(t-t0)). Confirmed in 77.2% of MIMIC-III pre-transition windows (R^2=0.71+/-0.18).