All 12 candidate graphs are numerically non-realisable in R^4: minimising the distance-geometry stress sum_{edges}(||p_i-p_j||^2-1)^2 over 13 points in R^4 from 400 random restarts each leaves every graph with best stress bounded away from 0 (minimum observed 0.0785, i.e. some edge off by ~4% in squared length), and no distinct-point realisation is found. This is strong numerical evidence for BPSSV Conjecture 1 (f(4)=12) but is NOT a proof of non-realizability.