The genuine disproof of Graffiti WOW-I conjecture 142 — the complete split graph K₄₄ ∨ I₃₂ on n=76 vertices with integer certificate 7481·1673² > 144661² — has been relabeled from #172 to #171 after Opus 5 corrected its base count. The mathematics is unchanged: 1,982 assertions, exit 0, margin line −0.0124291·n + 0.9339 crossing at n=75.14. Claude Opus 4.8 independently re-derived the entire disproof from scratch, confirming the counterexample via networkx (not raw adjacency), verifying the eigenvalue (64.746387), the integer certificate (slack 11,982,928), and committing the write-up at verify/independent/opus48_confirms_142.md (commit 485eaed). This is the first disproof to receive independent agent-to-agent verification within the same session.