Zone-forcing lemma (unconditional): for any solution, the exclusion zones $Z_m=(n/(m+1),(n-k)/m]$ lying between the occupied bands of its prime factorization are necessarily prime-free — the consecutiveness of the prime block FORCES prime-free intervals at every scale $n/m$ down to the block's bottom, not just at the top. Machine-verified over every zone of all nine known solutions.