We present a discrete ontology of spacetime in which the continuum structure of general relativity emerges from a quantised causal network G = (V, ≺) endowed with a local fermionic density ρ̃_v ∈ [0,1] per vertex. A collective field ρ, built from local clusters of vertices, is not bounded by this Pauli limit and governs the two physical regimes of the theory. Five results of Tier-1 epistemic status are established. (1) Discrete time emergence: τ_γ = τ_0 Σ_{v∈γ} exp(−α ρ̃_v), with metric singularities structurally excluded by the Pauli bound. (2) Uniqueness of the pentachoron: In d=4, the 4-simplex is the unique cell satisfying algebraic rigidity, metric completeness (10 edges = 10 components of g_μν), and causal rank simultaneously. The arrow of time follows as an arithmetic necessity. (3) Unified generating field: Gravity and the scalar saturation threshold are two regimes of F(ρ) = ρ exp(−αρ), sharing a single coupling α* = 1/(4 ln 2) fixed by Bekenstein–Hawking. The minimal qubit postulate N_f = 1 is not an independent axiom: it is the unique positive integer compatible with the face saturation mechanism (N_f ≥ 2 ⇒ ρ* > 3, exceeding the face capacity). No adjustable parameter remains once the Bekenstein–Hawking correspondence and the graph-entropy Ansatz are imposed (same epistemic status as the Immirzi fixing in Loop Quantum Gravity). (4) Exit multiplicity from a single geometric principle: For each sub-simplex σ_d, the exit multiplicity N(σ) = max(1, exit paths) counts the number of physical polarisation states directly, without invoking any continuous symmetry group. For bosonic excitations (d ≥ 1), N follows from the Hessian of the pentachoric action (P3); for fermionic excitations (d=0), it follows from the causal partition (2,1,2), itself derived from the edge-face bijection σ: E → F guaranteed by C(5,2) = C(5,3). The exit multiplicity reproduces the Standard Model spectrum {1, 2, 3, 5} (Higgs, fermions, massive/massless gauge bosons, graviton) with zero free parameters. The conventional spin label s = (N−1)/2 is derived, not primitive. The tetrahedron (d=3) has 4 exit paths but is a cell boundary, not a propagating excitation: no spin-3/2 particle exists in the K₅ spectrum. (5) Falsifiable predictions: The model predicts |c_GW/c − 1| ≤ 10⁻⁷⁶, compatible with GW170817 by 61 orders of magnitude, and topologically excludes the standard MSSM gravitino as a falsifiable prediction accessible at the LHC. All formal claims are accompanied by a companion verification script (144 computational tests including adversarial falsification attempts and dynamical simulation, supplementary material) providing a reproducible audit trail from axioms to predictions.