This Paper 3 working preprint replaces part of the Paper 2 proxy chain with a single reduced boundary-value problem along the extra coordinate. It tests whether the Paper 2 requirements for localization, pressure retention, late relic suppression, and radiation-like conserved stress can coexist in one coupled transport-proxy solver target. The result is a non-empty but tight reduced branch, plus a sharper blocker: the radiation-like equation of state is compatible but not dynamically selected, and the heavy drain cannot itself be the thermal EOS carrier. The manuscript does not derive baryogenesis, observable-domain coherence, or phenomenological safety.
Francisco Javier Vera Gómez (Thu,) studied this question.