We report the first high-stress boundary simulation for the Guiuan anchor node, ramping atmospheric loading from the 12.4 TJ baseline (P99) to a 15 TJ threshold event using the Waldron GMCV network. Four critical results are recorded under Protocol V3.1: (1) Micro-fracture onset at 13.84 TJ — structural ceiling of the Graphene-Hemp-Concrete (GHC) matrix, representing a thinner safety margin than baseline projections suggested; (2) Torsional amplitude spike to 0.415 rad (delta = 0.086 vs baseline 0.382, gray zone — not falsified but stressed); (3) Mycelial thermal dissipation stabilizing a +48 degrees C core spike in 3.8 seconds; (4) kappaOI response latency of 14.6 milliseconds — first direct timing measurement of the organoid intelligence layer. Self-healing rate dipped to 92.7% at peak stress, recovering to 98.1% — consistent with k(D) = ln(phi) x phi^2D branch survival prediction (P55). The tether survives the 15 TJ event. The 13.84 TJ micro-fracture threshold is recorded as the honest structural ceiling without revision. Four new pre-registered conjectures PC-P100-01 through PC-P100-04. Protocol V3.1 honest framing enforced. Surviving does not mean confirmed. Data decides.