We propose a novel cosmological framework, the Kerr-Salpeter Model, postulating that the observable universe is situated within the interior of a hyper-massive Kerr black hole in a 4-dimensional parent universe. We demonstrate that the observed cosmic acceleration, traditionally attributed to "Dark Energy," is a macroscopic manifestation of centrifugal pressure derived from the parent black hole’s frame-dragging. By applying 1+3 Covariant Macroscopic Gravity, we derive a regularized FLRW-like background with a persistent chiral signature ($\langle g_{t\phi} \rangle \neq 0$), yielding an effective cosmological constant $\Lambda_{eff} = \omega_{\mu\nu}\omega^{\mu\nu}/c^2$. This model replaces the inflationary paradigm with a Wands Duality occurring during the parent star’s gravitational collapse, analytically deriving the primordial scalar spectral index ($n_s \approx 0.965$) as a direct function of the parent's rotational kinetic energy ($w \approx -0.003$). We resolve the Hubble tension through a geometric elongation factor $\Gamma = 13/12$, originating from the topological variance of the macroscopic rotational shear. Furthermore, we address the Big Bang singularity via a non-singular Einstein-Cartan bounce, which generates the CP-violating torsion necessary for gravitational baryogenesis. Internal stability against mass inflation at the Cauchy horizon is ensured through fractal Kerr-de Sitter boundary conditions. The framework provides a precise prediction for the cosmic birefringence angle ($\beta \approx 0.41^\circ$) and aligns the observed entropy ($10^{122} k_B$) with the local Bousso bound. Finally, we propose experimental falsifiability via spin-squeezed atom interferometry, establishing a definitive path to detect global cosmological vorticity.