Whatsapp Coexistence Integration

Hi! I'm Adriano, founder of Conexto Tecnologia Digital (conexto.com.br) — a Brazilian B2B SaaS for restaurants (reservations, waitlist, loyalty, CRM, etc.). I'm looking for a specialist for a focused engagement. Tech context: Laravel 12 + Livewire 3.6, MySQL, Redis, Docker. Multi-tenant. Currently using YCloud as our WhatsApp BSP. What we built: An in-house integration with Meta Embedded Signup in Coexistence mode (featureType: whatsapp_business_app_onboarding) — so each restaurant client can connect their own WhatsApp Business number to the platform without switching numbers. Current state: - 128 Pest tests passing (unit + feature, with Http::fake() mocks for the Meta Graph API) - 0 Larastan errors on the feature files - Webhook endpoint validated by Meta (GET verification challenge returned 200 OK via ngrok) - All 4 webhook fields subscribed (account_update, history, smb_app_state_sync, smb_message_echoes) - All Coexistence-specific handlers implemented (sync progress, decline error 2593109, account events, etc.) Important: we have NOT completed a real end-to-end onboarding yet. Test code coverage is solid, but no actual customer has gone through the popup → code exchange → token → real webhook flow. Why not: I had a Meta account ban during Embedded Signup testing in previous development (different account). I stopped before completing onboarding to avoid repeating the issue without proper safeguards in place. What I need from you: 1. Review what's built and validate the implementation against Meta's current requirements 2. Plan and execute a safe end-to-end test with a real customer (we have a separate company with a different CNPJ that could be the test customer) 3. Help with App Review submission (Advanced Access for whatsapp_business_management + whatsapp_business_messaging), including the demo video Looking forward to hearing from you! Adriano Galhardo