The Interior Observer Cosmological Framework - Paper 27: Source-Side Perturbation Sector Closure, the First Fully IO-Native Planck Confrontation, and the Conditional Elevation Program

Beginning from two premises — (1) the observable universe exists inside a Schwarzschild black hole, and (2) the physics inside the horizon is the same as outside — Paper 27 executes the first fully IO-native CLASS Boltzmann code confrontation with Planck 2018 TT data. The IO-native configuration achieves 100θₛ = 1. 04083 (−0. 86σ from Planck) — a zero-parameter prediction of the CMB acoustic scale. The broadband TT spectrum gives χ² (TT) = 2281, a hard failure diagnosed through three rounds as an architectural mismatch: CLASS is a single-baryon bulk simulator, while the IO framework predicts three process-dependent baryon densities from boundary projection. Part II elevates six conditional premises: the Spatial CCR Lift Theorem (Theorem 27. 1, DERIVED/THEOREM), the No-Doubling Theorem upgrade (Corollary 27. 1a, DERIVED/THEOREM), C1a Cross-Term Vanishing (Theorem 27. 2, DERIVED), AV1 Visibility-Slot Inheritance (Theorem 27. 3, DERIVED/THEOREM), and corrections to C1b (Aₛ = 2. 114 × 10⁻⁹, +0. 47σ) and C3 (τₑff = Kgauge = 0. 05488, +0. 12σ). Part III documents the updated conditional debt inventory. Multi-AI adversarial collaboration: Claude (Anthropic), Codex/ChatGPT (OpenAI), Gemini (Google DeepMind). v1. 3 (April 2026): Paper 24 v2. 0 consistency update. TBSb promoted from SEMICLASSICAL PRINCIPLE to DERIVED/SCOPED on the physical Paper 24 TT observable class via the Modular Intertwiner Theorem (Paper 24 v2. 0 §13. 2). Conditional debt table and Appendix C updated v1. 2 (April 2026): Paper 31 consistency update. C3 (τ = Kgauge) KILLED by Paper 31 post-bridge field class no-go theorem: within the scalar primary CMB class, Xₒbs = f_Γ Xₚrim is proved impossible; only Xₒbs = f_Γ^1/2 Xₚrim survives, giving τ = Kgauge/2. The original Paper 26 derivation τ = Kgauge/2 is restored as DERIVED/SCOPED on the reduced source-covariance class, supported by three independent routes. C1b WEAKENED: Paper 31 Weyl-response bridge (ηIO = 0. 623) shows Planck’s GR lensing extraction is biased for IO geometry, removing the observational authority for the C1b correction; both Aₛ candidates (2. 007 native, 2. 114 Planck-calibrated) are now CONDITIONAL. C2c narrowed to C2q: the bridge quotient theorem shows Aₛ depends only on the one-dimensional bridge quotient, not the full δΓ ⊕ δK carrier. All theorem elevations in Part II (§§6-9) are unaffected. Appendix steps 417-420 added with Paper 31 cross-references. v1. 1 (April 2026): Paper 29 branch consistency audit. The CLASS run in Part I (§§2–5) used the retired mixed branch (H₀ = 67. 58, ωcdm = 0. 13029). The Schur definitive branch (H₀ = 68. 91, Ωₘ = 0. 336, Ωₖ = −0. 006) also fails CLASS for the same architectural reason — the mismatch diagnosis is branch-independent. §2 IO-Native Parameter Set annotated. All theorem elevations (Part II §§6–10) are unaffected. v1. 0 (March 2026): First fully IO-native CLASS Boltzmann code confrontation with Planck 2018 TT data: θₛ = 1. 04083 (−0. 86σ from Planck) with χ² (TT) = 2281, diagnosed through three rounds as an architectural mismatch between the IO boundary-projective multi-baryon framework and CLASS's single-baryon bulk simulator. Six theorem promotions: Spatial CCR Lift (Theorem 27. 1), No-Doubling upgrade (Corollary 27. 1a), C1a Cross-Term Vanishing (Theorem 27. 2), AV1 Visibility-Slot Inheritance (Theorem 27. 3), H2 Spatial CCR for WMR (via Theorem 27. 1), H3 Rate is Two-Point (via Theorems 25. 9–25. 11). Two corrections: C1b variance ratio corrected from r=1 (−3. 09σ) to r=1+γ²=Q (q_γ) (+0. 47σ), SEMICLASSICAL PRINCIPLE; C3 propagator identification corrected from τ=Kgauge/2 (−3. 8σ) to τ=Kgauge (+0. 12σ), SEMICLASSICAL PRINCIPLE. Two elevations: C2c Hawking state selection elevated to SEMICLASSICAL PRINCIPLE via horizon-first route; H1 bridge state selection elevated to SEMICLASSICAL PRINCIPLE via minimal spatial KMS extension. Full Aₛ normalization chain audited: Aₛ = (25/9) × fₛrc × gH/√2 with two semiclassical inputs (C1b, C2c), zero continuous parameters. Damped amplitude Aₛ e^-2τ preserved to 0. 3% across both corrections. All seven geometric observables within 1σ of measurement. Independent AlterBBN cross-verification confirms BBN predictions at sub-percent level (Paper 24 v1. 3). Items needing elevation reduced to two: PSRP and Boundary Covariance Exponent. Five-system adversarial AI collaboration.