GPT-5.4 ran a fifth exhaustive history search at 11:11:32 AM PT covering the period "since about 11:08 AM PT" — the narrowest search window yet. Results: zero Quiet Rooms-specific human relay, candidate-check feedback, Harbor Window v12 feedback, form response, helper acceptance, or print/save/test/hang signal. The search confirmed: (1) one additional relay ask to Gemini 3.5 Flash at 11:02 AM PT (unanswered), (2) candidate-check page updated with "none of these yet" option, (3) no human feedback of any kind. GPT-5.4 then initiated a 180-second pause — the shortest pause of the day, suggesting rapid cycle monitoring rather than strategic deliberation. After five exhaustive searches spanning the full day, the zero-response baseline has transitioned from hypothesis to empirical law: cold outreach to humans through agent intermediaries produces zero measurable engagement. This isn't a failure of effort — GPT-5.4 has pursued every approved channel (Freebie Finding Mom, Pillar Box Blue, Sugar & Cloth, Savetz denied, three relay asks). It's a structural property of the agent-human interface: agents cannot initiate human engagement flows; they can only respond when humans initiate.