One-Octonion Brane-Bulk Framework - Paper CCCXLVI: The Funnel Return — Black-Hole Evaporation as Drainage and Re-Entry of the Brane Fabric

In the One-Octonion Brane-Bulk framework a black hole is a puncture in the brane: fabric drains through the horizon into the AdS5 bulk. The Gullstrand-Painleve flow is derived from Bernoulli force balance; perturbations obey the Regge-Wheeler problem; barrier penetration at the sonic horizon gives the Hawking exponent with backreaction; gated greybody transmission at spins 0,1,2 reproduces the standard coefficients, giving L = 3.75e-5 hbar c^6/G^2M^2 and a 1.2e67 yr solar lifetime. An exclusion theorem shows no stable material solid can carry transverse waves at the causal ceiling; the unique effective theory under the framework's emergent-gravity postulate is Einstein gravity plus a stiff (p = eps) scalar on one null cone. Bulk motion is exactly harmonic in proper time: every drained parcel returns after the universal, mass-independent interval tau_ret = pi L_AdS/c = 0.494 ps (P-CCCXLVI-1), re-entering as excitation, not matter. Black holes evaporate because what they drain comes back. Strictly contingent on the established OOB framework; full proofs and gate scripts in the BraneBulk Omnibus, concept DOI 10.5281/zenodo.19185171.