Observations of the nuclear modification factor (RAA) in central Pb—Pb collisions at √sN N = 2.76, 5.02, and 5.36 TeV exhibit a persistent, energy-independent suppression floor at RAA ≈ 0.15.We demonstrate that this stability is statistically inconsistent at > 2σ with the logarithmic energy dependence predicted by perturbative QCD and instead matches a parameter-free geometrictransparency prediction (Φ = 0.147) derived from a discrete Fibonacci-Tetrahedral Lattice (FTL)model. Furthermore, three-particle azimuthal correlations reveal a 6.8σ angular excess at 1.91 radians (109.47◦), corresponding to the tetrahedral vertex angle arccos(−1/3). This structural signature distinguishes the vacuum lattice from standard harmonic flow coefficients (vn). We propose a definitive test of the discrete vacuum hypothesis through the prediction of a quantized phase transition at √sN N = 8.66 TeV, where the RAA floor is expected to shift to ≈ 0.24.